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STAT 113 Week 15 (Apr 15)Work Sheet 10: Chapter 24**Write down the type of probability (joint, marginal or conditional) for each question on this worksheet**Here are counts from a study of all firearm-related deaths in Wisconsin between 2000 and 2002 for children and youth under the age of 25 where the type of firearm used was known. We want to compare the types of firearms used in homicides and in suicides. HandgunLong gunHomicides10617Suicides59166What percent of deaths were suicides and used handguns? 59/(106+59+17+166)=16.95%, jointWhat percent of homicides used long guns? 17/(106+17)=13.82%, conditionalLong guns were used in what percent of deaths?(17+166)/ (106+59+17+166)=52.59%, marginalHere is a table that breaks down Purdue’s 1697 faculty members by both gender and academic rank: FemaleMaleAssistant professors151254Associate professors154397Professors99642What percent of the faculty members are female? (151+154+99)/1697=23.81%, marginalAmong male faculty members, what is the percent who are professors? 642/(254+397+642) =49.65%, conditionalWhat percent of the faculty members are female associate professors? 154/1697=9.07%, jointWhat percent of female faculty members were associate professors or professors? (154+99)/(151+154+99)=62.62%, conditionalHow is the hatching of water python eggs influenced by the temperature of the snake’s nest? Researchers assigned newly laid eggs to one of three temperature: hot, neutral, or cold. Hot duplicated the extra warmth provided by the mother python, and cold duplicated the absence of the mother. Here are the data on the number of eggs and the number that hatched: Number of eggsHatchedCold2716Neutral5638Hot10475Make a two-way table of temperature by outcome (hatched or not)Not hatchedHatchedCold1116Neutral1838Hot2975What percent of newly laid eggs were assigned to cold? 27/187=14.44%, marginal What percent of newly laid eggs were assigned to neutral and hatched?38/187=20.32%, jointFind the conditional distribution of temperature for hatched eggs and draw a labeled bar graph to display this distribution. 16/129=12.40%, 38/129=29.46%, 75/129=58.14%, Below are the numbers of flights on time and delayed for Alaska Airlines at five airports in one month. On timeDelayedLos Angeles49762Phoenix22112San Diego21220San Francisco503102Seattle1841305Among the flights to Los Angeles, what percent of flights were delayed? 62/(497+62)=11.09%, conditional What percent of delayed flights were not flying to Los Angeles? 100%-62/(62+12+20+102+305)=87.62%, conditional Or (12+20+102+305)/(62+12+20+102+305)=87.62% What percent of flights were on time? (497+221+212+503+1841)/(497+221+212+503+1841+62+12+20+102+305)=86.72%, Marginal What percent of flights were on time and the destination is Phoenix or San Diego? (221+212)/total = 11.47%, joint ................
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