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1PartOne:MultipleChoices:1.Theprobabilitythatacontinuousrandomvariabletakesanyspecificvaluea.isequaltozerob.isatleast0.5c.dependsontheprobabilitydensityfunctiond.isverycloseto1.02.Anormaldistributionwithameanof0andastandarddeviationof1iscalleda.aprobabilitydensityfunctionb.anordinarynormalcurvec.astandardnormaldistributiond.noneofthesealternativesiscorrect3.AnegativevalueofZindicatesthata.thenumberofstandarddeviationsofanobservationistotherightofthemeanb.thenumberofstandarddeviationsofanobservationistotheleftofthemeanc.amistakehasbeenmadeincomputations,sinceZcannotbenegatived.thedatahasanegativemean4.Foracontinuousrandomvariablex,theprobabilitydensityfunctionf(x)representsa.theprobabilityatagivenvalueofxb.theareaunderthecurveatxc.theareaunderthecurvetotherightofxd.theheightofthefunctionatx5.Forthestandardnormalprobabilitydistribution,theareatotheleftofthemeanisa.-0.5b.0.5c.anyvaluebetween0to1d.16.Largervaluesofthestandarddeviationresultinanormalcurvethatisa.shiftedtotherightb.shiftedtotheleftc.narrowerandmorepeakedd.widerandflatter7.Acontinuousprobabilitydistributionthatisusefulindescribingthetime,orspace,betweenoccurrencesofaneventisa(n)a.normalprobabilitydistributionb.uniformprobabilitydistributionc.exponentialprobabilitydistributiond.Poissonprobabilitydistribution8.Considerabinomialprobabilityexperimentwithn=3andp=0.1.Then,theprobabilityofx=0isa.0.0000b.0.0001c.0.001d.0.72929.Acontinuousrandomvariablemayassumea.allvaluesinanintervalorcollectionofintervalsb.onlyintegervaluesinanintervalorcollectionofintervalsc.onlyfractionalvaluesinanintervalorcollectionofintervalsd.allthepositiveintegervaluesinaninterval10.Thehighestpointofanormalcurveoccursata.onestandarddeviationtotherightofthemeanb.twostandarddeviationstotherightofthemeanc.approximatelythreestandarddeviationstotherightofthemeand.themeanExhibit1Theassemblytimeforaproductisuniformlydistributedbetween6to10minutes.11.RefertoExhibit1.Theprobabilitydensityfunctionhaswhatvalueintheintervalbetween6and10?a.0.25b.4.00c.5.00d.zero12.RefertoExhibit1.Theprobabilityofassemblingtheproductbetween7to9minutesisa.zerob.0.50c.0.20d.113.RefertoExhibit1.Theprobabilityofassemblingtheproductinlessthan6minutesisa.zerob.0.50c.0.15d.114.RefertoExhibit1.Theprobabilityofassemblingtheproductin7minutesormoreisa.0.25b.0.75c.zerod.115.RefertoExhibit1.Theexpectedassemblytime(inminutes)isa.16b.2c.8d.416.RefertoExhibit1.Thestandarddeviationofassemblytime(inminutes)isapproximatelya.1.3333b.1.1547c.0.1111d.0.5773317.Centerofanormalcurveisa.alwaysequaltozerob.isthemeanofthedistributionc.cannotbenegatived.isthestandarddeviation18.Theuniform,normal,andexponentialdistributionsarea.allcontinuousprobabilitydistributionsb.alldiscreteprobabilitydistributionsc.canbeeithercontinuousordiscrete,dependingonthedatad.allthesamedistributions19.Whichofthefollowingisnotacharacteristicofthenormalprobabilitydistribution?a.Themean,median,andthemodeareequalb.Themeanofthedistributioncanbenegative,zero,orpositivec.Thedistributionissymmetricald.Thestandarddeviationmustbe120.Inastandardnormaldistribution,therangeofvaluesofzisfroma.minusinfinitytoinfinityb.-1to1c.0to1d.-3.09to3.0921.Parametersarea.numericalcharacteristicsofasampleb.numericalcharacteristicsofapopulationc.theaveragestakenfromasampled.numericalcharacteristicsofeitherasampleorapopulation22.Howmanysimplerandomsamplesofsize3canbeselectedfromapopulationofsize7?a.7b.21c.35d.34323.Apopulationconsistsof500elements.Wewanttodrawasimplerandomsampleof50elementsfromthispopulation.Onthefirstselection,theprobabilityofanelementbeingselectedisa.0.100b.0.010c.0.001d.0.00224.Thecloserthesamplemeanistothepopulationmean,a.thelargerthesamplingerrorb.thesmallerthesamplingerrorc.thesamplingerrorequals1d.Noneofthesealternativesiscorrect.425.Sincethesamplesizeisalwayssmallerthanthesizeofthepopulation,thesamplemeana.mustalwaysbesmallerthanthepopulationmeanb.mustbelargerthanthepopulationmeanc.mustbeequaltothepopulationmeand.canbesmaller,larger,orequaltothepopulationmean26.Asthesamplesizeincreases,thea.standarddeviationofthepopulationdecreasesb.populationmeanincreasesc.standarderrorofthemeandecreasesd.standarderrorofthemeanincreases27.Asimplerandomsamplefromaninfinitepopulationisasampleselectedsuchthata.eachelementisselectedindependentlyandfromthesamepopulationb.eachelementhasa0.5probabilityofbeingselectedc.eachelementhasaprobabilityofatleast0.5ofbeingselectedd.theprobabilityofbeingselectedchanges28.Inpointestimationa.datafromthepopulationisusedtoestimatethepopulationparameterb.datafromthesampleisusedtoestimatethepopulationparameterc.datafromthesampleisusedtoestimatethesamplestatisticd.themeanofthepopulationequalsthemeanofthesample29.Thesamplemeanisthepointestimatorofa.b.c.d.30.Theexpectedvalueoftherandomvariableisa.thestandarderrorb.thesamplesizec.thesizeofthepopulationd.Noneofthesealternativesiscorrect.31.Thestandarddeviationofallpossiblevaluesiscalledthea.standarderrorofproportionb.standarderrorofthemeanc.meandeviationd.centralvariation32.Wheneverthepopulationhasanormalprob