Question 1 - JustAnswer
Question 1 Many high school students take the AP tests in different subject areas.? In 2007, of the 211,693 students who took the calculus AB exam 102,598 of them were female and 109,095 of them were male ("AP exam scores," 2013).? Estimate the difference in proportion of female students taking the calculus AB exam versus male students taking the calculus AB exam using a 90% confidence level.?(i)? Enter the level of significance α used for this test:Enter in decimal form to nearest hundredth.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10???? 0.90ANSWER: 0.10? (ii)??Determine??p?^??female?exam?takers???and??p?^??male?exam?Enter both in decimal form to nearest ten-thousandth, separated by comma (no spaces)? Examples of correctly entered answers:? 0.0001,0.0341 ??0.0020,0.0500 ??0.3000,0.7115ANSWER: 0.4847, 0.5153?(iii)? Determine?Z score corresponding to desired confidence level Enter value in decimal form rounded to nearest thousandth.? Examples of correctly entered answers:2.013 ?? ?? –0.137??????? 0.600 ?????? 0.005ANSWER: 1.645?(iv)? Determine error bound of the proportion:Enter value in decimal form rounded to nearest ten-thousandth.? Examples of correctly entered answers:0.0000 ??? 0.0010 ??? 0.0300 ??? 0.6000 ???? 0.8147? ?? 2.0000ANSWER: 0.0025?(v)??Let "p1" refer to proportion of children diagnosed with ASD in Pennsylvania.? Let "p2" represent proportion of children diagnosed with ASD in Utah.? Determine the confidence interval of the proportion difference p1 – p2: Enter lower bound value to nearest ten-thousandth, followed by < , followed by "p1-p2" for proportion difference or "μ1-μ2" for mean, followed by <, followed by upper bound value to nearest ten-thousandth.? No spaces between any characters. Do not use italics.? Examples of correctly entered answers:0.7754<p1-p2<0.783113.1224<μ1-μ2<13.9976-9.7261<μ1-μ2<-8.0833ANSWER: -0.0331 < p1-p2 < -0.0278?(vi)? Using the confidence interval, select the correct description of the result of the survey:A.? We estimate with 90% confidence that the true proportion of female students taking the calculus AB exam is anywhere from 2.78% to 3.31% higher than the proportion of male students taking the calculus AB exam. B.? We estimate with 90% confidence that the true proportion of male students taking the calculus AB exam is anywhere from 2.78% to 3.31% lower than the proportion of female students taking the calculus AB exam. C.? We estimate with 90% confidence that the true mean population of female students taking the calculus AB exam is anywhere from 2.78% to 3.31% higher than the true mean population of male students taking the calculus AB exam. D.? We estimate with 90% confidence that the true proportion of female students taking the calculus AB exam is anywhere from 2.78% to 3.31% lower than the proportion of male students taking the calculus AB exam. Enter letter corresponding to most correct answerANSWER: DQuestion 2 Are there more children diagnosed with Autism Spectrum Disorder (ASD) in states that have larger urban areas over states that are mostly rural?? In the state of Pennsylvania, a fairly urban state, there are 245 eight year olds diagnosed with ASD out of 18,440 eight year olds evaluated.? In the state of Utah, a fairly rural state, there are 45 eight year olds diagnosed with ASD out of 2,123 eight year olds evaluated ("Autism and developmental," 2008).? Is there enough evidence to show that the proportion of children diagnosed with ASD in Pennsylvania is more than the proportion in Utah?? Test at the 1% level.(i)? Let?p1?= proportion of children diagnosed with ASD in Pennsylvania and?p2 = proportion of children diagnosed with ASD in Utah.? Which of the following statements correctly defines the null hypothesis HO?A.? p1 + p2 > 0B.??p1 + p2 = 0C.? μ1 = μ2D.??p1 = p2Enter letter corresponding to correct answerANSWER: D?(ii)? Let?p1?= proportion of children diagnosed with ASD in Pennsylvania and?p2 = proportion of children diagnosed with ASD in Utah.? Which of the following statements correctly defines the alternate hypothesis HA?A.? p1 – p2 < 0B.??p1 – p2 = 0C.? μ1 = μ2D.??p1 – p2 > 0Enter letter corresponding to correct answerANSWER: D(iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.01(iv)??Determine??p????Pennsylvania???and??p????Utah? Enter both in decimal form to nearest ten-thousandth, separated by comma (no spaces)? Examples of correctly entered answers:? 0.0001,0.0341 ??0.0020,0.0500 ??0.3000,0.5115ANSWER: 0.0133, 0.0212?(v)??Find?pooled?sample?proportion?p?????? Let?p????Pennsylvania??=?p????1??and?p????Utah??=?p????2? Enter in decimal form to nearest ten-thousandth.? Examples of correctly entered answers:? 0.0001 ? ?? 0.0020???? 0.0500 ???? 0.3000?? 0.5115ANSWER: 0.0141?(vi)? Calculate and enter test statisticEnter value in decimal form rounded to nearest thousandth, with appropriate sign (no spaces).? Examples of correctly entered answers:–2.014????? –0.370??????? +1.600??????? +11.009ANSWER: -2.924?(vii)? Using tables, calculator, or spreadsheet:? Determine and enter p-value corresponding to test statistic.Enter value in decimal form rounded to nearest thousandth.? Examples of correctly entered answers:0.000???? 0.001???? 0.030???? 0.600????? 0.814? ? ? 1.000ANSWER: 0.9983?(viii)? Comparing p-value and α value, which is the correct decision to make for this hypothesis test?? A.? Reject HoB.? Fail to reject HoC.? Accept HoD.? Accept HAEnter letter corresponding to correct answer. ANSWER: B.? Fail to reject Ho?(ix)? Select the statement that most correctly interprets the result of this test:A.? The result is not statistically significant at .01 level of significance.? Evidence supports the claim that the proportion of children diagnosed with ASD in Pennsylvania is more than the proportion of children diagnosed with ASD in Utah. B.? The result is statistically significant at .01 level of significance.? There is not enough evidence to show that the proportion of children diagnosed with ASD in Pennsylvania is more than the proportion of children diagnosed with ASD in Utah. C.? The result is not statistically significant at .01 level of significance.? There is not enough evidence to show that the proportion of children diagnosed with ASD in Pennsylvania is more than the proportion of children diagnosed with ASD in Utah. D.? The result is statistically significant at .01 level of significance.? Evidence supports the claim that the proportion of children diagnosed with ASD in Pennsylvania is more than the proportion of children diagnosed with ASD in Utah. Enter letter corresponding to most correct answerANSWER: CQuestion 3 All Fresh Seafood is a wholesale fish company based on the east coast of the U.S.? Catalina Offshore Products is a wholesale fish company based on the west coast of the U.S.? Table #9.2.5 contains prices from both companies for specific fish types ("Seafood online," 2013) ("Buy sushi grade," 2013).? Data is in following table:??FishAll Fresh Seafood PricesCatalina Offshore Products PricesCod19.9917.99Tilapi6.0013.99Farmed Salmon19.9922.99Organic Salmon24.9924.99Grouper Fillet29.9919.99Tuna28.9931.99Swordfish23.9923.99Sea Bass32.9923.99Striped Bass29.9914.99Do the data provide enough evidence to show that a west coast fish wholesaler is more expensive than an east coast wholesaler?? Test at the 5% level.(i)? Let μ1?= mean wholesale prices from west coast fishery.? Let μ2 = mean wholesale prices from east coast fishery .? Which of the following statements correctly defines the null hypothesis HO?A.? μ1 ? μ2 > 0? (μd > 0)B.? μ1 – μ2 = 0? (μd = 0)C.? μ1 – μ2 < 0? (μd < 0)D.? μ1 + μ2 = 0 Enter letter corresponding to correct answerANSWER: B(ii)? Let μ1?= mean wholesale prices from west coast fishery.? Let μ2 = mean wholesale prices from east coast fishery .? Which of the following statements correctly defines the alternate hypothesis HA?A.? μ1 ? μ2 > 0? (μd > 0)B.? μ1 – μ2 = 0? (μd = 0)C.? μ1 – μ2 < 0? (μd < 0)D.? μ1 + μ2 = 0 Enter letter corresponding to correct answerANSWER: A(iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.05 (iv)??Determine?sample?mean?of?differences??x????dEnter in decimal form to nearest ten-thousandth.? Examples of correctly entered answers:? 0.0001?0.0020?0.300011.2485ANSWER: 2.4456 ?(v)? Determine sample standard deviation of differences?sd? Enter in decimal form to nearest ten-thousandth.? Examples of correctly entered answers:? 0.0001 ? ?? 0.0020???? 0.0500 ???? 0.3000?? 0.5115ANSWER: 7.3994(vi)? Calculate and enter test statisticEnter value in decimal form rounded to nearest ten-thousandth, with appropriate sign (no spaces).? Examples of correctly entered answers:–2.0104????? –0.3070??????? +1.6000 ?????? +11.0019ANSWER: 0.9915(vii)? Determine degrees of freedom for the sample of differences dfd :Enter value in integer form.? Examples of correctly entered answers:2??? 5??? 9??? 23??? 77ANSWER: 8 ?(viii)? Using tables, calculator, or spreadsheet:? Determine and enter p-value corresponding to test statistic.Enter value in decimal form rounded to nearest ten-thousandth.? Examples of correctly entered answers:0.0001 ??? 0.0021???? 0.0305 ??? 0.6004 ???? 0.8143? ?? 1.0000ANSWER: 0.1752(ix)? Comparing p-value and α value, which is the correct decision to make for this hypothesis test?? A.? Reject HoB.? Fail to reject HoC.? Accept HoD.? Accept HAEnter letter corresponding to correct answer.?ANSWER: B (x)? Select the statement that most correctly interprets the result of this test:A.? The result is not statistically significant at .05 level of significance.? Sufficient evidence exists to support the claim that west coast fish wholesalers are more expensive than east coast wholesalers.B.? The result is not statistically significant at .05 level of significance.? There is not enough evidence to support the claim that west coast fish wholesalers are more expensive than east coast wholesalers.C.? The result is statistically significant at .05 level of significance.? There is not enough evidence to support the claim that west coast fish wholesalers are more expensive than east coast wholesalers.D.? The result is statistically significant at .05 level of significance.? Sufficient evidence exists to support the claim that west coast fish wholesalers are more expensive than east coast wholesalers.Enter letter corresponding to most correct answerANSWER: B Question 4 The British Department of Transportation studied to see if people avoid driving on Friday the 13th.?? They did a traffic count on a Friday and then again on a Friday the 13th at the same two locations ("Friday the 13th," 2013).? The data for each location on the two different dates is in following table:Table: Traffic CountDates6th13th1990, July1392461385481990, July1340121329081991, September1370551360181991, September1337321318431991, December1235521216411991, December1211391187231992, March1282931255321992, March1246311202491992, November1246091227701992, November117584117263?Let μ1?= mean traffic count on Friday the 6th.? Let μ2 =? mean traffic count on Friday the 13th.? Estimate the mean difference in traffic count between the 6th and the 13th using a 90% level. (i)??Determine?the?sample?mean?of?differences??x????d? Enter in decimal form to nearest tenth.?? ANSWER: 1835.8 ?(ii)? Determine sample standard deviation of differences?sd? Enter in decimal form to nearest hundredth.? Examples of correctly entered answers:? 0.01 ? ?? 0.20???? 0.35 ???? 3.00 ?ANSWER: 1176.01(iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.10 ?(iv)? Determine degrees of freedom for the sample of differences dfd :Enter value in integer form.? Examples of correctly entered answers:2??? 5??? 9??? 23??? 77ANSWER: 9 ?(v)? Determine t - score associated with critical value:? tcEnter in decimal form to nearest thousandth.? Examples of correctly entered answers:? 0.0011 ? ?? 0.020???? 0.500 ??? 0.371 ? ? 2.000ANSWER: 1.833 ?(vi)? Determine "error bound of the mean of difference"?E Enter value in decimal form rounded to nearest tenth.? Examples of correctly entered answers:2.0????? 0.3 ??? 1.6 ????? 11.7ANSWER: 681.7 ?(vii)? Determine confidence interval of the mean difference μdEnter lower bound value to nearest tenth, followed by < , followed by "μd" for mean difference, followed by <, followed by upper bound value to nearest tenth.? No spaces between any characters. Use "negative" sign if necessary.? Do not use italics or enter units of measure.? Examples of correctly entered answers:0.74<μd<0.7813.14<μd<13.96-9.72<μd<-8.08ANSWER: 1154.1 <μd<2517.5(viii)? Using the confidence interval, select the correct description of the result of the survey:A.? We estimate with 90% confidence that the true population mean traffic count between Friday the 6th and Friday the 13th is between 1154.1 and 2517.5. B.? We estimate with 90% confidence that the true mean difference in traffic counts between Friday the 6th and Friday the 13th falls outside 1154.1 and 2517.5. C.? We estimate with 90% confidence that the true sample mean traffic counts between Friday the 6th and Friday the 13th is between 1154.1 and 2517.5. D.? We estimate with 90% confidence that the true mean difference in traffic counts between Friday the 6th and Friday the 13th is between 1154.1 and 2517.5. Enter letter corresponding to most correct answerANSWER: D Question 5 The income of males in each state of the United States, including the District of Columbia and Puerto Rico, are given in Table 1, and the income of females is given in Table 2 ("Median income of," 2013):Table 1: Data of Income for Males$42,951$52,379$42,544$37,488$49,281$50,987$60,705$50,411$66,760$40,951$43,902$45,494$41,528$50,746$45,183$43,624$43,993$41,612$46,313$43,944$56,708$60,264$50,053$50,580$40,202$43,146$41,635$42,182$41,803$53,033$60,568$41,037$50,388$41,950$44,660$46,176$41,420$45,976$47,956$22,529$48,842$41,464$40,285$41,309$43,160$47,573$44,057$52,805$53,046$42,125$46,214$51,630????Table 2: Data of Income for Females$31,862$40,550$36,048$30,752$41,817$40,236$47,476$40,500$60,332$33,823$35,438$37,242$31,238$39,150$34,023$33,745$33,269$32,684$31,844$34,599$48,748$46,185$36,931$40,416$29,548$33,865$31,067$33,424$35,484$41,021$47,155$32,316$42,113$33,459$32,462$35,746$31,274$36,027$37,089$22,117$41,412$31,330$31,329$33,184$35,301$32,843$38,177$40,969$40,993$29,688$35,890$34,381????Is there enough evidence to show that the mean income of males is more than of females?? Test at the 1% level. (i)? Let μ1?= mean income of a male in 2013.? Let μ2 =? mean income of a female in 2013.? Which of the following statements correctly defines the null hypothesis HO?A.? μ1 ? μ2 = 0? (μ1 = μ2)B.? μ1 – μ2 < 0? (μ1 < μ2)C.? μ1 ? μ2 > 0? (μ1 > μ2)D.? μ1 + μ2 = 0 Enter letter corresponding to correct answerANSWER: A ?(ii)?? Let μ1?= mean income of a male in 2013.? Let μ2 =? mean income of a female in 2013.? Which of the following statements correctly defines the alternate hypothesis HA?A.? μ1 ? μ2 = 0? (μ1 = μ2)B.? μ1 – μ2 < 0? (μ1 < μ2)C.? μ1 ? μ2 > 0? (μ1 > μ2)D.? μ1 + μ2 = 0 ?Enter letter corresponding to correct answerANSWER: C ?(iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.01?(iv)??For?sample?from?population?with?mean?=?μ?1??:??????????Determine?sample?mean?x????1??and?sample?standard?deviation?s?1??Enter sample mean in decimal form to nearest hundredth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.27,2.31?0.27,0.06-10.30,0.79ANSWER: 46453.31, 7030.71 (v)??For?sample?from?population?with?mean?=?μ?2??:???????Determine?sample?mean?x????2??and?sample?standard?deviation?s?Enter sample mean in decimal form to nearest hundredth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.27,2.31?0.27,0.06-10.30,0.79?ANSWER: 36511.00, 6138.12 (vi)? Determine degrees of freedom df :Enter value in decimal form rounded down to nearest whole number.? Examples of correctly entered answers:1? ?23? ?72ANSWER: 102 ?(vii)? Determine test statistic:Enter value in decimal form rounded to nearest thousandth.? Examples of correctly entered answers:2.014????? 3.070??????? 16.000 ?????? 110.019ANSWER: 7.682 (viii)? Using tables, calculator, or spreadsheet:? Determine and enter p-value corresponding to test statistic.Enter value in decimal form rounded to nearest ten-thousandth.? Examples of correctly entered answers:0.0001 ??? 0.0021???? 0.0305 ??? 0.6004 ???? 0.8143? ?? 1.0000ANSWER: 0.0000 (ix)? Comparing p-value and α value, which is the correct decision to make for this hypothesis test?? A.? Reject HoB.? Fail to reject HoC.? Accept HoD.? Accept HAEnter letter corresponding to correct answer.?ANSWER:A (x)? Select the statement that most correctly interprets the result of this test:A.? The result is not statistically significant at .01 level of significance.? Sufficient evidence exists to support the claim that the mean income of males is more than of females. . B.? The result is not statistically significant at .01 level of significance.? There is not enough evidence to support the claim that the mean income of males is more than of females. C.? The result is statistically significant at .01 level of significance.? Sufficient evidence exists to support the claim that the mean income of males is more than of females. D.? The result is statistically significant at .01 level of significance.? There is not enough evidence to support the claim that the mean income of males is more than of females. Enter letter corresponding to most correct answerANSWER: C Question 6 A study was conducted that measured the total brain volume (TBV) (in mm3) of patients that had schizophrenia and patients that are considered normal.? Table #1 contains the TBV of the normal patients and Table #2 contains the TBV of schizophrenia patients ("SOCR data Oct2009," 2013).?Table #1: Total Brain Volume (in mm3) of Normal Patients16634071583940129947015351371431890157869814535101650348128897113663461326402150300514747901317156144104514634981650207152304514416361432033142041614801711360810141021315748081502702120334413197371688990129264115125711635918????Table #2: Total Brain Volume (in mm3) of Schizophrenia Patients1331777148788610660751297327149998318619911368378147689114437751337827165825815881321690182156941311770021387893148376316889501563593131788514202491363859123897912866381325525158857314762541648209135405413546491636119??????Is there enough evidence to show that the patients with schizophrenia have less TBV on average than a patient that is considered normal?? Test at the 10% level. (i)? Let μ1?= mean TBV of patients that are considered normal.? Let μ2 = mean TBV of patients that had schizophrenia.? Which of the following statements correctly defines the null hypothesis HO?A.? μ1 + μ2 = 0B.? μ1 – μ2 < 0? (μ1 < μ2)C.? μ1 ? μ2 > 0? (μ1 > μ2)D.? μ1 ? μ2 = 0? (μ1 = μ2)Enter letter corresponding to correct answerANSWER: D (ii)?? Let μ1?= mean TBV of patients that are considered normal.? Let μ2 = mean TBV of patients that had schizophrenia.? Which of the following statements correctly defines the alternate hypothesis HA?A.? μ1 ? μ2 = 0? (μ1 = μ2)B.? μ1 – μ2 < 0? (μ1 < μ2)C.? μ1 ? μ2 > 0? (μ1 > μ2)D.? μ1 + μ2 = 0 Enter letter corresponding to correct answerANSWER: C (iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.10 (iv)??For?sample?from?population?with?mean?=?μ1?:?Determine?sample?mean?ˉx1?and?sample?standard?deviation?s1 Enter sample mean in integer form (no decimals), then comma, then sample standard deviation in integer form.? Examples of correctly entered answers:? 13145,1211-112845,13187ANSWER: 146339, 125458 (v)??For?sample?from?population?with?mean?=?μ2?:???????Determine?sample?mean?x?2?and?sample?standard?deviation?s2Enter sample mean in integer form (no decimals), then comma, then sample standard deviation in integer form.? Examples of correctly entered answers:? 13145,1211-112845,13187?ANSWER: 1451293, 171932 (vi)? Determine degrees of freedom df :Enter value in decimal form rounded down to nearest whole number.? Examples of correctly entered answers:2? ? ? 3? ? ? ? 16? ? ? ? 110ANSWER: 61 (vii)? Determine test statistic:Enter value in decimal form rounded to nearest ten-thousandth.? Examples of correctly entered answers:0.0104????? 3.0370??????? 16.5000 ?????? 110.0819ANSWER: 0.3168 (viii)? Using tables, calculator, or spreadsheet:? Determine and enter p-value corresponding to test statistic.Enter value in decimal form rounded to nearest ten-thousandth.? Examples of correctly entered answers:0.0001 ??? 0.0021???? 0.0305 ??? 0.6004 ???? 0.8143? ?? 1.0000?ANSWER: 0.3762 (ix)? Comparing p-value and α value, which is the correct decision to make for this hypothesis test?? A.? Reject HoB.? Fail to reject HoC.? Accept HoD.? Accept HAEnter letter corresponding to correct answer.ANSWER: B (x)? Select the statement that most correctly interprets the result of this test:A.? The result is not statistically significant at .10 level of significance.? Sufficient evidence exists to support the claim that patients with schizophrenia have less TBV on average than a patient that is considered normal. B.? The result is not statistically significant at .10 level of significance.? There is not enough evidence to support the claim that patients with schizophrenia have less TBV on average than a patient that is considered normal. C.? The result is statistically significant at .10 level of significance.? Sufficient evidence exists to support the claim that patients with schizophrenia have less TBV on average than a patient that is considered normal. D.? The result is statistically significant at .10 level of significance.? There is not enough evidence to support the claim that patients with schizophrenia have less TBV on average than a patient that is considered normal. Enter letter corresponding to most correct answerANSWER: B Question 7 A study was conducted that measured the total brain volume (TBV) (in mm3) of patients that had schizophrenia and patients that are considered normal.? Table #1 contains the TBV of the normal patients and Table #2 contains the TBV of schizophrenia patients ("SOCR data Oct2009," 2013).?Table #1: Total Brain Volume (in mm3) of Normal Patients16634071583940129947015351371431890157869814535101650348128897113663461326402150300514747901317156144104514634981650207152304514416361432033142041614801711360810141021315748081502702120334413197371688990129264115125711635918????Table #2: Total Brain Volume (in mm3) of Schizophrenia Patients1331777148788610660751297327149998318619911368378147689114437751337827165825815881321690182156941311770021387893148376316889501563593131788514202491363859123897912866381325525158857314762541648209135405413546491636119?????Let μ1?= mean TBV of patients that are considered normal.? Let μ2 =? mean TBV of patients that had schizophrenia.? Compute a 90% confidence interval for the difference in TBV of normal patients and patients with Schizophrenia.(i)??For?the?sample?from?population?with?mean?=?μ?1??:??????Determine?sample?mean?x????1??and?sample?standard?deviation?s?1??i??For?the?sample?from?population?with?mean?=?μ1?:??????Determine?sample?mean?x?1?and?sample?standard?deviation?s1 ?Enter sample mean to nearest integer, then comma, then sample standard deviation to nearest integer.? Examples of correctly entered answers:? 1332,112-15478,3651ANSWER: 146339, 125458 (ii)??For?the?sample?from?the?population?with?mean?=?μ?2??:??????Determine?sample?mean?x????2??and?sample?standard?deviation?s?2??Enter sample mean to nearest integer, then comma, then sample standard deviation to nearest integer.? Examples of correctly entered answers:? 1332,112-15478,3651ANSWER: 1451293, 171932 ?(iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.10 ?(iv)? Determine degrees of freedom df :Enter value rounded DOWN to nearest integer. ANSWER: 61 ?(v)? Determine t - score associated with critical value:? tcEnter in decimal form to nearest thousandth.? Examples of correctly entered answers:? 0.0011 ? ?? 0.020???? 0.500 ??? 0.371 ? ? 2.000?ANSWER: 1.6702 (vi)? Determine "error bound of the mean"?E Enter value rounded to nearest integer.? ANSWER: 63621 (vii) Determine confidence interval estimate of the difference μ1 – μ2 :Enter lower bound value to nearest integer, followed by < , followed by "μ1-μ2" for difference, followed by <, followed by upper bound value to nearest integer.? No spaces between any characters. Do not use italics, but if mathematically necessary use negative signs.? Examples of correctly entered answers:0.77<μ1-μ2<0.7813.12<μ1-μ2<13.94-9.73<μ1-μ2<-8.08?ANSWER: -51565 < μ1-μ2< 75677(viii)? Using the confidence interval, select the most correct description of the result of the survey:A.? We estimate with 90% confidence that the mean TBV of people considered normal is anywhere from 51565 mm3 more to 75677 mm3 less than the mean TBV for people with schizophrenia. B.? We estimate with 90% confidence that the true proportional TBV of people considered normal is anywhere from 51565 mm3 less to 75677 mm3 more than the mean TBV for people with schizophrenia. C.? We estimate with 90% confidence that the sample mean TBV of people considered normal is anywhere from 51565 mm3 less to 75677 mm3 more than the mean TBV for people with schizophrenia. D.? We estimate with 90% confidence that the true mean TBV of people considered normal is anywhere from 51565 mm3 less to 75677 mm3 more than the mean TBV for people with schizophrenia. Enter letter corresponding to most correct answer?ANSWER: DQuestion 8The number of cell phones per 100 residents in countries in Europe is given in Table #1 for the year 2010.? The number of cell phones per 100 residents in countries of the Americas is given in Table #2 also for the year 2010 ("Population reference bureau," 2013).?Table #1: Number of Cell Phones per 100 Residents in Europe100761001307584112841381331181341261881299364128124122109121127152966399951511471239567671181251101151401151417798102102112118118542312112647?Table #2: Number of Cell Phones per 100 Residents in the Americas1581171061595350786688924231507286113505870109373285101756955115957386157100119811138710596???Let μ1?= mean number of cell phones per 100 residents in countries of Europe.? Let μ2 = mean number of cell phones per 100 residents in countries of the Americas.? Find the 98% confidence interval for the difference in mean number of cell phones per 100 residents in Europe and the Americas.(i)??For?the?sample?from?population?with?mean?=?μ?1??:??????Determine?sample?mean?x????1??and?sample?standard?deviation?s?1??Enter sample mean in decimal form to nearest ten-thousandth, then comma, then sample standard deviation in decimal form to nearest ten-thousandth.? Examples of correctly entered answers:? 13.2027,2.3471?0.2700,0.0006-10.3150,0.0790ANSWER: 108.1509, 29.9650 (ii)??For?the?sample?from?the?population?with?mean?=?μ2?:??????Determine?sample?mean?x?2?and?sample?standard?deviation?s2Enter sample mean in decimal form to nearest ten-thousandth, then comma, then sample standard deviation in decimal form to nearest ten-thousandth.? Examples of correctly entered answers:? 13.2027,2.3471?0.2700,0.0006-10.3150,0.0790ANSWER: 87.2051, 35.1554 (iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.02? (iv)? Determine degrees of freedom df :Enter value rounded DOWN to nearest integer. ANSWER: 90 ?(v)? Determine t - score associated with critical value:? tcEnter in decimal form to nearest thousandth.? Examples of correctly entered answers:? 0.0011 ? ?? 0.020???? 0.500 ??? 0.371 ? ? 2.000?ANSWER: 2.3685(vi)? Determine "error bound of the mean"?E Enter value in decimal form rounded to nearest thousandth.? Examples of correctly entered answers:2.014????? 3.070??????? 16.000 ?????? 110.019ANSWER: 16.582 (vii) Determine confidence interval estimate of the difference μ1 – μ2 :Enter lower bound value to nearest ten-thousandth, followed by < , followed by "μ1-μ2" for difference, followed by <, followed by upper bound value to nearest ten-thousandth.? No spaces between any characters. Do not use italics, but if mathematically necessary use negative signs.? Examples of correctly entered answers:0.0077<μ1-μ2<0.078013.1012<μ1-μ2<18.3941-9.7300<μ1-μ2<-3.0008?ANSWER: 4.3641< μ1-μ2 < 37.5276 (viii)? Using the confidence interval, select the most correct description of the result of the survey:A.? We estimate with 98% confidence that the sample mean number of cell phones per 100 residents in countries of Europe is anywhere from 4.3641 to 37.5276 more than the mean number of cell phones per 100 residents in countries of the Americas. B.? We estimate with 98% confidence that the true mean number of cell phones per 100 residents in countries of Europe is anywhere from 4.3641 to 37.5276 more than the mean number of cell phones per 100 residents in countries of the Americas. C.? We estimate with 98% confidence that the true proportion of cell phones per 100 residents in countries of Europe is anywhere from 4.3641 to 37.5276 more than the mean number of cell phones per 100 residents in countries of the Americas. D.? We estimate with 98% confidence that the mean number of cell phones per 100 residents in countries of Europe is anywhere from 4.3641 to 37.5276 less than the mean number of cell phones per 100 residents in countries of the Americas. Enter letter corresponding to most correct answerANSWER: BQuestion 9 Levi-Strauss Co manufactures clothing.? The quality control department measures weekly values of different suppliers for the percentage difference of waste between the layout on the computer and the actual waste when the clothing is made (called run-up).? The data is in the following table, and there are some negative values because sometimes the supplier is able to layout the pattern better than the computer ("Waste run up," 2013).?Table #11.3.3: Run-ups for Different Plants Making Levi Strauss ClothingPlant 1Plant 2Plant 3Plant 4Plant 51.216.412.111.52410.1-69.710.2-3.7-2-11.67.43.88.21.5-1.3-2.18.39.2-3410.16.6-9.3-0.7174.710.283.23.84.68.815.82.74.33.92.722.3-3.210.43.65.13.1-1.74.29.611.216.82.48.59.85.911.30.36.36.51312.33.595.76.816.9-0.87.15.114.5?19.44.33.45.2?2.819.7-0.87.3?133-3.97.1?42.77.60.93.4?1.470.21.50.7?38.5???2.46???1.32.9???Do the data show that there is a difference between some of the suppliers?? Test at the 1% level**********************************************************************Let x1 = percentage difference of waste between the layout on the computer and the actual waste when the clothing is made (called run-up) from plant 1Let x2 = percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 2Let x3 = percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 3Let x4 = percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 4Let x5 = percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 5Let μ1 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 1Let μ2 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 2Let μ3 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 3Let μ4 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 4Let μ5 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 5(i)? Which of the following statements correctly defines the null hypothesis HO?A.? All five mean percentage differences are equalB.? Two of the mean percentage differences are not equalC.? At least four of the mean percentage differences are equalD. At least two of the mean percentage differences are not equal Enter letter corresponding to correct answerANSWER: A Let μ1 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 1Let μ2 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 2Let μ3 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 3Let μ4 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 4Let μ5 = mean percentage difference of waste between the layout on the computer and the actual waste of run-up from plant 5(ii)? Which of the following statements correctly defines the alternate hypothesis HA?A.? All five mean percentage differences are equalB.? Two of the mean percentage differences are not equalC.? At least four of the mean percentage differences are equalD.? At least two of the mean percentage differences are not equalEnter letter corresponding to correct answerANSWER: D (iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.01 ?(iv)? Calculate sample mean and sample standard deviation for Plant 1 sample?Enter sample mean in decimal form to nearest hundredth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.27,2.31?0.27,0.06-10.30,0.79ANSWER: 4.52, 10.03 (v)? Calculate sample mean and sample standard deviation for Plant 2 sampleEnter sample mean in decimal form to nearest hundredth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.27,2.31?0.27,0.06-10.30,0.79ANSWER: 8.83, 15.35 (vi)? Calculate sample mean and sample standard deviation for Plant 3 sampleEnter sample mean in decimal form to nearest hundredth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.27,2.31?0.27,0.06-10.30,0.79?ANSWER: 4.83, 4.40 (vii)? Calculate sample mean and sample standard deviation for Plant 4 sampleEnter sample mean in decimal form to nearest hundredth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.27,2.31?0.27,0.06-10.30,0.79?ANSWER: 7.49, 3.66 (viii)? Calculate sample mean and sample standard deviation for Plant 5 sampleEnter sample mean in decimal form to nearest hundredth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.27,2.31?0.27,0.06-10.30,0.79?ANSWER: 10.38, 9.56 (ix)? Using technology, determine F ratio test statistic and corresponding p-value.Use "CTRL-click" to access link.? Enter test statistic to nearest hundredth, then enter comma, then enter p-value to nearest thousandth.? Examples of correctly entered responses:12.33,0.004? ? ? ? ??7.50,0.0006.77,0.504ANSWER: 1.16, 0.334(x)? Comparing p-value and α value, which is the correct decision to make for this hypothesis test?? A.? Reject HoB.? Fail to reject HoC.? Accept HoD.? Accept HAEnter letter corresponding to correct answer.?ANSWER: B (xi)? Select the statement that most correctly interprets the result of this test:A.? The result is not statistically significant at .01 level of significance.? Sufficient evidence exists to support the claim that there is a difference between some of the suppliers. B.? The result is statistically significant at .01 level of significance.? There is not enough evidence to support the claim that there is a difference between some of the suppliers.C.? The result is statistically significant at .01 level of significance.? Sufficient evidence exists to support the claim that there is a difference between some of the suppliers.D.? The result is not statistically significant at .01 level of significance.? There is not enough evidence to support the claim?that there is a difference between some of the suppliers.Enter letter corresponding to most correct answerANSWER: D Question 10 A study was undertaken to see how accurate food labeling for calories on food that is considered "reduced calorie".? The group measured the amount of calories for each item of food and then found the percent difference between measured and labeled food. The group also looked at food that was nationally advertised, regionally distributed, or locally prepared.? The data is in the following table ("Calories data file," 2013).?Table:? Percent Differences Between Measured and Labeled FoodNational AdvertisedRegionally DistributedLocally Prepared24115-284660-622508251456396-116.5801017951328315-3?-414?-434?-1842?10??5??3??-7??3??-0.5??-10??6???Do the data indicate that at least two of the mean percent differences between the three groups are different?? Test at the 10% level.**********************************************************************Let x1 = percent difference of calories between measured and labeled reduced calorie food that is nationally advertisedLet x2 = percent difference of calories between measured and labeled reduced calorie food that is regionally distributedLet x3 = percent difference of calories between measured and labeled reduced calorie food that is prepared locally.Let μ1 = mean percent difference of calories between measured and labeled reduced calorie foods that are nationally advertisedLet μ2 = mean percent difference of calories between measured and labeled reduced calorie foods that are regionally distributedLet μ3 = mean percent difference of calories between measured and labeled reduced calorie foods that are prepared locally.?(i)? Which of the following statements correctly defines the null hypothesis HO?A.? None of the three mean percentage differences are equalB.? At least two of the mean percentage differences are not equal C.? At least two of the mean percentage differences are equalD.? All three mean percentage differences are equalEnter letter corresponding to correct answerANSWER: D Let μ1 = mean percent difference of calories between measured and labeled reduced calorie foods that are nationally advertisedLet μ2 = mean percent difference of calories between measured and labeled reduced calorie foods that are regionally distributedLet μ3 = mean percent difference of calories between measured and labeled reduced calorie foods that are prepared locally.?(ii)? Which of the following statements correctly defines the alternate hypothesis HA?A.? None of the three mean percentage differences are equalB.? At least two of the mean percentage differences are not equal C.? At least two of the mean percentage differences are equalD.? All three mean percentage differences are equalEnter letter corresp onding to correct answer?ANSWER: B ?(iii)? Enter the level of significance α used for this test:Enter in decimal form.? Examples of correctly entered answers:? 0.01 ?? 0.02??? 0.05??? 0.10ANSWER: 0.10 (iv)? Calculate sample mean and sample standard deviation for sample percent differences between measured and labeled food that is advertised nationally.Enter sample mean in decimal form to nearest thousandth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.278,2.31?0.274,0.06-10.301,0.79ANSWER: 0.125, 10.52(v)? Calculate sample mean and sample standard deviation for for sample percent differences between measured and labeled food that is distributed regionally.Enter sample mean in decimal form to nearest thousandth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.278,2.31?0.274,0.06-10.301,0.79 ANSWER: 25.125, 16.07 ?(vi)? Calculate sample mean and sample standard deviation for sample percent differences between measured and labeled food that is prepared locally.Enter sample mean in decimal form to nearest thousandth, then comma, then sample standard deviation in decimal form to nearest hundredth.? Examples of correctly entered answers:? 13.278,2.31?0.274,0.06-10.301,0.79ANSWER: 81.750, 83.97 ?(vii)? Determine F ratio test statistic and corresponding p-value.Use "CTRL-click" to access link.? Enter test statistic to nearest hundredth, then enter comma, then enter p-value to nearest ten-thousandth.? Examples of correctly entered responses:12.33,0.0040??????????7.50,0.00016.77,0.5049ANSWER: 12.98, 0.000(viii)? Comparing p-value and α value, which is the correct decision to make for this hypothesis test?? A.? Accept HAB.? Fail to reject HoC.? Accept HoD.? Reject Ho? Enter letter corresponding to correct answer.ANSWER: D(ix)? Select the statement that most correctly interprets the result of this test:A.? The result is not statistically significant at .10 level of significance.? Sufficient evidence exists to support the claim that at least two of the mean percent differences between the three groups are different.? B.? The result is statistically significant at .10 level of significance.? There is not enough evidence to support the claim that at least two of the mean percent differences between the three groups are different.? C.? The result is statistically significant at .10 level of significance.? Sufficient evidence exists to support the claim that at least two of the mean percent differences between the three groups are different.? D.? The result is not statistically significant at .10 level of significance.? There is not enough evidence to support the claim?that at least two of the mean percent differences between the three groups are different.? Enter letter corresponding to most correct answerANSWER: B Question 11A claim is made that when parents use the XSORT method of gender selection during in-vitro fertilization, the proportion of baby girls is greater than 0.5.? The latest results show that among 945 babies born to couples using the XSORT method of gender selection, 879 were girls.? Identify the null and alternative hypothesis for this test.H0: p = 0.5 ; HA: p > 0.5H0: p ≤ 0.5 ; HA: p > 0.5H0: p = 0.5 ; HA: p ≠ 0.5H0: p = 0.5 ; HA: p < 0.5Answer: H0: p = 0.5 ; HA: p > 0.5Question 12 A 0.05 significance level is used for a hypothesis test of the claim that when parents use the XSORT method of gender selection, the proportion of baby girls is different from 0.5.? Assume that the data consists of 55 girls born in 100 births.? Identify the null and alternative hypothesis for this test.H0: p = 0.5 ; HA: p > 0.5H0: p = 0.5 ; HA: p < 0.5H0: p = 0.5 ; HA: p ≠ 0.5None of these AnswersH0: p ≤ 0.5 ; HA: p > 0.5Answer: H0: p = 0.5 ; HA: p ≠ 0.5Question 13A 0.05 significance level is used for a hypothesis test of the claim that when parents use the XSORT method of gender selection, the proportion of baby girls is different from 0.5.? Assume that the data consists of 55 girls born in 100 births.? Identify the null and alternative hypothesis for this test.? What is the value of α?α = 0.05α = 0.01α = 0.95None of these Answersα = 0.99Answer: α = 0.05Question 14A 0.05 significance level is used for a hypothesis test of the claim that when parents use the XSORT method of gender selection, the proportion of baby girls is different from 0.5.? Assume that the data consists of 55 girls born in 100 births.? ?Is this a two-tailed, left-tailed, or right-tailed test?left-tailedright-tailedtwo-tailedAnswer: two-tailedQuestion 15A 0.05 significance level is used for a hypothesis test of the claim that when parents use the XSORT method of gender selection, the proportion of baby girls is different from 0.5.? Assume that the data consists of 55 girls born in 100 births.? ?What is the value of the test statistic associated with this hypothesis test?None of these Answersz = 1.00t = -1.00z = -1.00t = 1.00Answer: z = 1.00Question 16 A 0.05 significance level is used for a hypothesis test of the claim that when parents use the XSORT method of gender selection, the proportion of baby girls is different from 0.5.? Assume that the data consists of 55 girls born in 100 births.? ?What is the p-value associated with this test?0.15870.15990.31970.3173None of these AnswersAnswer: 0.3173Question 17 Vincent randomly selected a bag of M&Ms from a randomly selected gas station as he was driving down the interstate.? Being bored while riding in the car, he decided to evaluate his green M&Ms.? From this simple random sample, there were 19 green M&Ms with a sample mean weight of 0.8635 grams and a sample standard deviation of 0.0570 grams.? Use a 0.05 significance level to test the claim that the mean weight of all M&Ms is equal to 0.8535 (which is the mean weight required so that M&Ms have the weight printed on the packaged label).What is the null and alternative hypotheses for this test?HO: μ = 0.8535; HA: μ > 0.8535HO: μ = 0.8535; HA: μ ≠ 0.8535HO: μ < 0.8635; HA: μ > 0.8635HO: μ < 0.8635; HA: μ ≠ 0.8635None of these answersAnswer: HO: μ = 0.8535; HA: μ ≠ 0.8535Question 18 Vincent randomly selected a bag of M&Ms from a randomly selected gas station as he was driving down the interstate.? Being bored while riding in the car, he decided to evaluate his green M&Ms.? From this simple random sample, there were 19 green M&Ms with a sample mean weight of 0.8635 grams and a sample standard deviation of 0.0570 grams.? Use a 0.05 significance level to test the claim that the mean weight of all M&Ms is equal to 0.8535 (which is the mean weight required so that M&Ms have the weight printed on the packaged label).Is this a two-tailed, left-tailed, or right-tailed test?two-tailedleft-tailedright-tailedAnswer: two-tailedQuestion 19 Vincent randomly selected a bag of M&Ms from a randomly selected gas station as he was driving down the interstate.? Being bored while riding in the car, he decided to evaluate his green M&Ms.? From this simple random sample, there were 19 green M&Ms with a sample mean weight of 0.8635 grams and a sample standard deviation of 0.0570 grams.? Use a 0.05 significance level to test the claim that the mean weight of all M&Ms is equal to 0.8535 (which is the mean weight required so that M&Ms have the weight printed on the packaged label).What is the value of the test statistic associated with this hypothesis test?t = -0.765z = 3.333None of these Answersz = 0.765Answer: None of these AnswersQuestion 20 Vincent randomly selected a bag of M&Ms from a randomly selected gas station as he was driving down the interstate.? Being bored while riding in the car, he decided to evaluate his green M&Ms.? From this simple random sample, there were 19 green M&Ms with a sample mean weight of 0.8635 grams and a sample standard deviation of 0.0570 grams.? Use a 0.05 significance level to test the claim that the mean weight of all M&Ms is equal to 0.8535 (which is the mean weight required so that M&Ms have the weight printed on the packaged label).What is the P-value associated with this hypothesis test?0.77290.4543None of the Above0.00190.2271Answer: 0.4543Question 21 Vincent randomly selected a bag of M&Ms from a randomly selected gas station as he was driving down the interstate.? Being bored while riding in the car, he decided to evaluate his green M&Ms.? From this simple random sample, there were 19 green M&Ms with a sample mean weight of 0.8635 grams and a sample standard deviation of 0.0570 grams.? Use a 0.05 significance level to test the claim that the mean weight of all M&Ms is equal to 0.8535 (which is the mean weight required so that M&Ms have the weight printed on the packaged label).What is the critical value associated with this hypothesis test?1.33042.10092.0930None of These Answers1.7341Answer: 2.1009Question 22 Vincent randomly selected a bag of M&Ms from a randomly selected gas station as he was driving down the interstate.? Being bored while riding in the car, he decided to evaluate his green M&Ms.? From this simple random sample, there were 19 green M&Ms with a sample mean weight of 0.8635 grams and a sample standard deviation of 0.0570 grams.? Use a 0.05 significance level to test the claim that the mean weight of all M&Ms is equal to 0.8535 (which is the mean weight required so that M&Ms have the weight printed on the packaged label).What is the result of this hypothesis test?Because P-value is greater than the critical region, we Accept the Null Hypothesis. ?There is not sufficient evidence to warrant rejection of the claim that the mean weight of all green M&Ms is equal to 0.8535.?Because P-value is greater than the critical region, we Fail to Reject the Null Hypothesis. ?There is not sufficient evidence to warrant rejection of the claim that the mean weight of all green M&Ms is equal to 0.8535.?Because P-value is greater than the critical region, we Reject the Null Hypothesis. ?There is sufficient evidence to warrant rejection of the claim that the mean weight of all green M&Ms is equal to 0.8535.?Because P-value is less than the critical region, we Reject the Null Hypothesis. ?There is sufficient evidence to warrant rejection of the claim that the mean weight of all green M&Ms is equal to 0.8535.?Answer: Because P-value is greater than the critical region, we Fail to Reject the Null Hypothesis. ?There is not sufficient evidence to warrant rejection of the claim that the mean weight of all green M&Ms is equal to 0.8535.?Question 23 The Mars Candy Company claims that 13% of its M&M candies are brown, but a simple random sample of 100 M&M candies has only 8 brown M&M candies.? Suppose we want to use the sample data to construct a 98% confidence interval estimate of the proportion of brown M&M candies.?Which test statistic is used to compute the margin of error in this situation?None of These Answersz-statisticChi-squared statistict-statisticAnswer: z-statisticQuestion 24 ?The Mars Candy Company claims that 13% of its M&M candies are brown, but a simple random sample of 100 M&M candies has only 8 brown M&M candies.?Suppose we want to use the sample data to construct a 98% confidence interval estimate of the proportion of brown M&M candies.? Compute the Margin of Error for a 98% confidence interval estimate of the proportion of brown M&M candies.2.32630.0672.45730.063Answer: 0.063Question 25 The Mars Candy Company claims that 13% of its M&M candies are brown, but a simple random sample of 100 M&M candies has only 8 brown M&M candies.?Use the sample data to construct a 98% confidence interval estimate of the proportion of brown M&M candies.?0.017 < 0.13 < 0.1430.017 < p < 0.1430.067 < 0.13 < 0.193None of These Answers0.067 < p < 0.193Answer: 0.017 < p < 0.143 ................
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