（E）1-P（X<85）
9.Atelevisionnewseditorwouldliketoknowhowlocalregisteredvoterswouldrespondtothequestion,"Areyouinfavoroftheschoolbondmeasurethatwillbevotedoninanupcomingspecialelection?
"Atelevisionsurveyisconductedduringabreakintheeveningnewsbylistingtwotelephonenumberssidebysideonthescreen,oneforviewerstocalliftheyapproveofthebondmeasure,andtheothertocalliftheydisapprove.Thissurveymethodcouldproducebiasedresultsforanumberofreasons.Whichoneofthefollowingisthemostobviousreason?
（A）Itusesastratifiedsampleratherthanasimplerandomsample.
（B）Peoplewhofeelstronglyabouttheissuearemorelikelytorespond.
（C）Viewersshouldbetoldabouttheissuesbeforethesurveyisconducted.
（D）Someregisteredvoterswhocallmightnotvoteintheelection.
（E）Thewordingofthequestionisbiased.
10.Ahighschoolphysicsteacherwasconductinganexperimentwithhisclassonthelengthoftimeitwilltakeamarbletorolldownaslopedchute.Theclassranrepeatedtrialsinordertodeterminetherelationshipbetweenthelength,incentimeters,oftheslopedchuteandthetime,inseconds,forthemarbletorolldownthechute.Alinearrelationshipwasobservedandthecorrelationcoefficientwas0.964.Afterdiscussingtheirresults,theteacherinstructedthestudentstoconvertallofthelengthmeasurementstometersbutleavethetimeinseconds.Whateffectwillthishaveonthecorrelationofthetwovariables?
（A）Becausethestandarddeviationofthelengthsinmeterswillbeonehundredthofthestandard
deviationofthelengthsincentimeters,thecorrelationwilldecreasebyonehundredthto0.954.
（B）Becausethestandarddeviationofthelengthsinmeterswillbeonehundredthofthestandard
deviationofthelengthsincentimeters,thecorrelationwilldecreaseproportionallyto0.00964.
（C）Becausechangingfromcentimeterstometersdoesnotaffectthevalueofthecorrelation,the
correlationwillremain0.964.
（D）Becauseonlythelengthmeasurementshavebeenchanged,thecorrelationwilldecrease
substantially.
（E）Becausemetersareamuchmorecommonmeasurementforlengthindeterminingspeed,thelinear
relationshipofthedatawillbestrongerandthusthecorrelationwillincreasesubstantially.
11.Juliegeneratesasampleof20randomintegersbetween0and9inclusive.Sherecordsthenumberof6'sinthesample.Sherepeatsthisprocess99moretimes,recordingthenumberof6'sineachsample.Whatkindofdistributionhasshesimulated?
（A）Thesamplingdistributionofthesampleproportionwithn=20andp=0.6
（B）Thesamplingdistributionofthesampleproportionwithn=100andp=0.1
（C）Thebinomialdistributionwithn=20andp=0.1
（D）Thebinomialdistributionwithn=100andp=0.1
（E）Thebinomialdistributionwithn=20andp=0.6
n
Mean
Median
SampleI
21
42.6
45.0
SampleII
26
49.2
48.5
12.Thetableaboveshowsthesamplesize,themean,andthemedianfortwosamplesofmeasurements.Whatisthemedianforthecombinedsampleof47measurements?
（A）
（B）
（C）
（D）
（E）Itcannotbedeterminedfromtheinformationgiven.
13.Dan,atraineratthePopularGym,wasinterestedincomparinglevelsofphysicalfitnessofstudentsattendinganearbycommunitycollegeandthoseattendinga4-yearcollegeintown.Heselectedarandomsampleof320studentsfromthecommunitycollege.Themeanandstandarddeviationoftheirfitnessscoreswere95and10,respectively.Danalsoselectedarandomsampleof320studentsfroma4-yearcollege.Themeanandstandarddeviationoftheirfitnessscoreswere
92and13,respectively.Hethenconductedatwo-sidedt-testthatresultedinat-valueof3.27.Whichofthefollowingisanappropriateconclusionfromthisstudy?
（A）Becausethesamplemeansonlydifferedby3,thepopulationmeansarenotsignificantlydifferent.
（B）Becausethesecondgrouphadalargerstandarddeviation,theirmeanfitnessscoreissignificantly
higher.
（C）Becausethesecondgrouphadalargerstandarddeviation,themeanfitnessscoreofthefirstgroup
issignificantlyhigher.
（D）Becausethep-valueislessthanα=0.05,themeanfitnessscoresforthetwogroupsofstudents
aresignificantlydifferent.
（E）Becausethep-valueisgreaterthanα=0.05,themeanfitnessscoresforthetwogroupsofstudents
aresignificantlydifferent.
14.Aresearcherwishestotestanewdrugdevelopedtotreathypertension（highbloodpressure）.Agroupof40hypertensivemenand60hypertensivewomenistobeused.Theexperimenterrandomlyassigns20ofthemenand30ofthewomentotheplaceboandassignstheresttothetreatment.Themajorreasonforseparateassignmentformenandwomenisthat
（A）itisalargestudywith100subjects
（B）thenewdrugmayaffectmenandwomendifferently
（C）thenewdrugmayaffecthypertensiveandnonhypertensivepeopledifferently
（D）thisdesignusesmatchedpairstodetectthenew-drugeffect
（E）theremustbeanequalnumberofsubjectsinboththeplacebogroupandthetreatmentgroup.
15.Thehistogramsbelowrepresentthedistributionoffivedifferentdatasets,eachcontaining28integers,from1through7,inclusive.Thehorizontalandverticalscalesarethesameforallgraphs.Whichgraphrepresentsthedatasetwiththelargeststandarddeviation.
（A）（B）（C）
（D）（E）
16.LynnisplanningtoflyfromNewYorktoLosAngelesandwilltaketheAirtightAirlinesflightthatleavesat8A.M.TheWebsitesheusedtomakeherreservationstatesthattheprobabilitythattheflightwillarriveinLosAngelesontimeis0.70.Ofthefollowing,whichisthemostreasonableexplanationforhowthatprobabilitycouldhavebeenestimated?
（A）Byusinganextendedweatherforecastforthedateofherflight,whichshoweda30%chanceof
badweather
（B）Bymakingassumptionsabouthowairplaneswork,andfactoringallofthoseassumptionsintoan
equationtoarriveattheprobability
（C）Fromthefactthat,ofallairlineflightsarrivinginCalifornia,70%arriveontime
（D）Fromthefactthat,ofallairlineflightsintheUnitedStates,70%arriveontime
（E）Fromthefactthat,onallpreviousdaysthisparticularflighthadbeenscheduled,ithadarrivedon
time70%ofthosedays
17.Inanexperiment,twodifferentspeciesofflowerswerecrossbred.Theresultingflowersfromthiscrossbreedingexperimentwereclassified,bycolorofflowerandstigma,intooneoffourgroups,asshowninthetablebelow.
FlowerTypeResultingfromCrossbreeding
NumberofFlowersObservedwithTheseColors
I:
Magentalowerwithgreenstigma
115
II:
Magentaflowerwithredstigma
49
III:
Redflowerwithgreenstigma
32
IV:
Redflowerwithredstigma
21
Abiologistexpectedthattheratioof9:
3:
3:
1fortheflowertypesI:
II:
III:
IV,respectively,wouldresultfromthiscrossbreedingexperiment.Fromthedataabove,a
valueofapproximately8.04wascomputed.Aretheobservedresultsinconsistentwiththeexpectedratioatthe5percentlevelofsignificance?
（A）Yes,becausethecomputed
valueisgreat
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