Question 1



|Question 1 |0.5 points   |Save   |

|  |Determine whether a correlation coefficient of r = –0.405 is significant at the 5% level for a | | | | |

| |sample size of 22. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |r is not significant at 5%. | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |r is significant at 5%. | | | | |

| | | | | | |

|Question 2 |0.5 points   |Save   |

|  |If a student's rank in a class of 400 students is 44, find the student's percentile rank. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |88 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |89 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |87 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |90 | | | | |

| | | | | | |

|Question 3 |0.5 points   |Save   |

|  |Find the equation of the regression line. | | | | |

| |[pic][pic] | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |y = –1.2 + 2.4x | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |y = 1.2 + 2.4x | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |y = 2.4 + 1.2x | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |y = –2.4 + 1.2x | | | | |

| | | | | | |

|Question 4 |0.5 points   |Save   |

|  |To select a Convenience or Incidental sample, an intact group of subjects that represent the | | | | |

| |population is selected. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |stratified | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |random | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |cluster | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |systematic | | | | |

| | | | | | |

|Question 5 |0.5 points   |Save   |

|  |Use a scatter plot to determine the relationship between the x values and the y values. | | | | |

| |[pic][pic] | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |No relationship | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |Nonlinear relationship | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |Positive linear relationship | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |Negative linear relationship | | | | |

| | | | | | |

|Question 6 |0.5 points   |Save   |

|  |Find the area under the normal distribution curve between z = 1.52 and z = 2.43. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |0.929 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.436 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.493 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.057 | | | | |

| | | | | | |

| Question 7 |0.5 points   |Save   |

|  |Find the value for the correlation coefficient r. | | | | |

| |[pic][pic] | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |–0.073 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |–0.094 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |–0.203 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |–0.149 | | | | |

| | | | | | |

|Question 8 |0.5 points   |Save   |

|  |Use the equation of the regression line to predict y when x = 20. | | | | |

| |[pic][pic] | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |45.5 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |50 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |40 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |48.5 | | | | |

| | | | | | |

| |  | | | | |

| | | | | | |

| |  | | | | |

| | | | | | |

|Question 9 |0.5 points   |Save   |

|  |Which statement is true for a statistical study? | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |The sample is a subset of the population. | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |The population is a subset of the sample. | | | | |

| | | | | | |

|Question 10 |0.5 points   |Save   |

|  |The area under a normal distribution curve that lies within one standard deviation of the mean | | | | |

| |is approximately _____. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |95% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |99.7% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |68% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |65% | | | | |

| | | | | | |

|Question 11 |0.5 points   |Save   |

|  |Find the value for the correlation coefficient r. | | | | |

| |[pic][pic] | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |0.763 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.874 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.551 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.968 | | | | |

| | | | | | |

|Question 12 |0.5 points   |Save   |

|  |Find the area under the normal distribution curve to the right of z = –3.24. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |0.499 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |–0.499 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.999 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.001 | | | | |

| | | | | | |

|Question 13 |0.5 points   |Save   |

|  |Find the area under the normal distribution curve to the right of z = –1.03. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |0.151 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |–0.349 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.349 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.849 | | | | |

| | | | | | |

|Question 14 |0.5 points   |Save   |

|  |Kate scored in the 95th percentile rank on an exam. If 400 students took the exam, how many | | | | |

| |students scored lower than Kate? | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |379 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |381 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |378 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |380 | | | | |

| | | | | | |

|  Question 15 |0.5 points   |Save   |

|  |The average amount customers at a certain grocery store spend yearly is $636.55. Assume the | | | | |

| |variable is normally distributed. If the standard deviation is $89.46, find the probability | | | | |

| |that a randomly selected customer spends between $550.67 and $836.94. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |0.144 = 14.4% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.820 = 82.0% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.156 = 15.6% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.943 = 94.3% | | | | |

| | | | | | |

|Question 16 |0.5 points   |Save   |

|  |A data set of size 19 has correlation coefficient of r = –0.432. Test the significance of r at | | | | |

| |the 5% level and at the 1% level. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |r is significant at 5% and at 1%. | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |r is significant at 5%, but not at 1%. | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |r is is not significant at 5% or at 1%. | | | | |

| | | | | | |

|Question 17 |0.5 points   |Save   |

|  |The average hourly wage of employees of a certain company is $9.83. Assume the variable is | | | | |

| |normally distributed. If the standard deviation is $4.58, find the probability that a randomly | | | | |

| |selected employee earns less than $5.43. | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |0.313 = 31.3% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.332 = 33.2% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.168 = 16.8% | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |0.345 = 34.5% | | | | |

| | | | | | |

|Question 18 |0.5 points   |Save   |

|  |Find Q1, Q2, and Q3 for the data set below. | | | | |

| |5.4 2.0 6.8 3.1 2.9 4.7 2.1 5.0 1.9 3.4 | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |Q1 = 2.05, Q2 = 3.1, Q3 = 5.2 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |Q1 = 2.05, Q2 = 3.25, Q3 = 5.2 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |Q1 = 2.1, Q2 = 3.25, Q3 = 5.0 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |Q1 = 2.1, Q2 = 3.4, Q3 = 5.0 | | | | |

| | | | | | |

|[pic]  Question 19 |0.5 points   |Save   |

|  |Which of the following is not a property of a normal distribution? | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |It never touches the x-axis. | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |It is continuous. | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |The mean, median, and mode are equal. | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |It is bimodal (i.e., it has two modes). | | | | |

| | | | | | |

|[pic]  Question 20 |0.5 points   |Save   |

|  |Find the standard deviation. | | | | |

| |44 46 33 10 50 27 | | | | |

| |[pic] | | | | |

| |[pic][pic] | | | | |

| | | | | | |

| |1694 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |186.67 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |14.97 | | | | |

| | | | | | |

| |[pic] | | | | |

| | | | | | |

| |224 | | | | |

| | | | | | |

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download