Level 3 Mathematics and Statistics (Statistics) (91586) 2017
Transcript of Level 3 Mathematics and Statistics (Statistics) (91586) 2017
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© Mana Tohu Mātauranga o Aotearoa, 2017. Pūmau te mana. Kia kaua rawa he wāhi o tēnei tuhinga e whakahuatia ki te kore te whakaaetanga tuatahi a te Mana Tohu Mātauranga o Aotearoa.
MĀ TE KAIMĀKA ANAKE
TAPEKE
Te Pāngarau me te Tauanga (Tauanga), Kaupae 3, 2017
91586M Te whakahāngai i ngā tuari tūponotanga hei whakaoti rapanga
9.30 i te ata Rāhina 27 Whiringa-ā-rangi 2017 Whiwhinga: Whā
Paetae Kaiaka KairangiTe whakahāngai i ngā tuari tūponotanga hei whakaoti rapanga.
Te whakahāngai i ngā tuari tūponotanga mā te whakaaro whaipānga hei whakaoti rapanga.
Te whakahāngai i ngā tuari tūponotanga mā te whakaaro waitara hōhonu hei whakaoti rapanga.
Tirohia mēnā e rite ana te Tau Ākonga ā-Motu (NSN) kei runga i tō puka whakauru ki te tau kei runga i tēnei whārangi.
Me whakamātau koe i ngā tūmahi KATOA kei roto i tēnei pukapuka.
Tuhia ō mahinga KATOA.
Tirohia mēnā kei a koe te Pukapuka Tikanga Tātai me ngā Tūtohi L3–STATMF.
Mēnā ka hiahia whārangi atu anō mō ō tuhinga, whakamahia ngā whārangi wātea kei muri o tēnei pukapuka, ka āta tohu ai i ngā tau tūmahi
Tirohia mēnā e tika ana te raupapatanga o ngā whārangi 2 – 15 kei roto i tēnei pukapuka, ka mutu, kāore tētahi o aua whārangi i te takoto kau.
HOATU TE PUKAPUKA NEI KI TE KAIWHAKAHAERE HEI TE MUTUNGA O TE WHAKAMĀTAUTAU.
Te Pāngarau me te Tauanga (Tauanga) 91586M, 2017
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TŪMAHI TUATAHI
(a) Kataeaterahingawaimōtehoroihīreretewhakatauiramātētahitaurangimatapōkereewhaiuaraanaiwaengaite20ritamete200rita.Mekīkoterahingawaikatinowhakamahiapeainahoroihīrereanahe50rita.
(i) Mātewhakamahiitētahitauiratuaritūponotangatōtika,tātaihiahewhakatautatamōteōrauongāhoroihīrereheitiihoite50ritatewaikawhakamahia.
(ii) Mātewhakamahiitētahitauiratuaritūponotangatōtika,tātaihiahewhakatautatamōteōrauongāhoroihīrerehenuiakeite40ritatewaikawhakamahia.
(b) KataeaengākaihautūwakangātaupāngawhakaterengaGPSwaeapūkororerekētewhakamahiheiwhiwhiwhakatautatamōteroaotewākitetaekitētahiwāhi.IwhakahaerehiaherangahauheitūhurahepēheatetōtikaongāwhakatautatawāhaerengamaiitētahitaupāngawhakaterengaGPSake.Mōiahaerengairotoiterangahau,iwhakatauriteatewāhaerengawhakatautatakitewāhaerengatika,ā,itātaihiatererekētangapūrawa(tirohiatetūtohiiraro).
Haerenga Wā haerenga whakatau tata Wā haerenga tika
Te rerekētanga pūrawa i waenga i te wā haerenga whakatau tata me te wā
haerenga tika1 10.4meneti 11.3meneti 0.9meneti2 6.5meneti 5.2meneti 1.3meneti3 3.9meneti 3.9meneti 0meneti… … … …
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(i) Mekī,kote15%ongāhaerengaitutukiirotoiterangahaukakīia“kāoreitetika”mātewhakamahiitererekētangapūrawa.
Mēnātekaungāhaerengaitīpakohiamatapōkerehiaiterangahau,mātewhakamahiitetauiratōtika,tātaihiatetūponotangaewhāitenuirawaongāhaerengaikīia“kāoreitetika”.
(ii) Parahautiatewhakamahiitetuaritūponotangamōtōtuhingakitewāhanga(i).
(iii) Kotererekētangapūrawatautohariteiwaengaitewāhaerengawhakatautatametewāhaerengatikamōngāhaerengairotoitēneirangahauhe3.5meneti,meteinemahoraote2.8meneti.Ikiteaanōeterangahaue87%ongāhaerengaheitiihoiterimamenetingārerekētangapūrawa.
MatapakitiangāpūtakeeRUAikoreaietikakitewhakamahiitētahituarimāoriheiwhakatauiraingārerekētangapūrawaiwaengaitewāhaerengawhakatautatametewāhaerengatikamōngāhaerenga.
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QUESTION ONE
(a) Theamountofwaterusedwhentakingashowercanbemodelledbyarandomvariablethattakesonvaluesbetween20litresand200litres.Themostlikelyamountofwaterusedwhentakingashoweris50litres.
(i) Usinganappropriateprobabilitydistributionmodel,calculateanestimateforthepercentageofshowersthatuselessthan50litresofwater.
(ii) Usinganappropriateprobabilitydistributionmodel,calculateanestimateforthepercentageofshowersthatusemorethan40litresofwater.
(b) CardriverscanusevariousmobilephoneGPSnavigationappstogetanestimateofthetimeitwilltaketotraveltoadestination.AstudywascarriedouttoinvestigatehowaccuratethetraveltimeestimateswerefromoneparticularGPSnavigationapp.Foreachtripinthestudy,theestimatedtraveltimewascomparedtotheactualtraveltime,andtheabsolutedifferencecalculated(seethetablebelow).
Trip Estimated travel time Actual travel timeAbsolute difference
between estimated travel time and actual travel time
1 10.4minutes 11.3minutes 0.9minutes2 6.5minutes 5.2minutes 1.3minutes3 3.9minutes 3.9minutes 0minutes… … … …
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(i) Suppose15%oftripsmadeduringthestudywereclassifiedas“notaccurate”usingtheabsolutedifference.
Iftentripsfromthestudywerechosenatrandom,usinganappropriatemodel,calculatetheprobabilitythatatmostfourofthetripswereclassifiedas“notaccurate”.
(ii) Justifytheuseoftheprobabilitydistributionforyouranswerinpart(i).
(iii) Themeanabsolutedifferencebetweentheestimatedtraveltimeandtheactualtraveltimefortripsinthisstudywas3.5minutes,withastandarddeviationof2.8minutes.Thestudyalsofoundthat87%oftripshadabsolutedifferencesoflessthanfiveminutes.
DiscussTWOreasonswhyitwouldbeinappropriatetouseanormaldistributiontomodeltheabsolutedifferencesbetweentheestimatedtraveltimeandtheactualtraveltimefortrips.
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TŪMAHI TUARUA
(a) Ewhakaatuanatetūtohiiraroneiitetuaritūponotangaotetaurangimatapōkere,X.
x 0 1 2 3 4
P(X = x) 0.11 0.21 0.24 0.25 0.19
(i) E(X)=2.2.
TātaihiateVAR(X ).
(ii) KotetaurangimatapōkereYkuawhaiVAR(Y)=1.5376.
VAR(X + Y )=5.5696.
HewehekēaX me Y?
Tautokonatōtuhingakingātauākītauangaetōtikaana.
(b) KataeatepaemahanatohariteotētahirūmanohoiAotearoaitētahipōtakuruatewhakatauiramātētahituarimāori,metetautohariteote17.8°Cmeteinemahoraote2.1°C.
(i) Mātewhakamahiitēneitauira,iwaengaiēheauaraeruakotōtūmanakomōte95%owaenganuiongāpaemahanatoharitemōngārūmanohoiAotearoaitētahipōtakurua?
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(ii) MatapakitiakiaKOTAHIteāhuatangaheiwhakaaroaroinawhakatauirahiatepaemahanatohariteitētahirūmanohoiAotearoaitētahipōtakurua?
(iii) MēkīerimangāwhareitīpakohiamatapōkerehiaiAotearoa,ā,ikiteaitewhāoēneiwhareirarotepaemahanatohariteoterūmanohoitetahipōtakuruaite16°C.
Heitipeatetūponotangakakiteaewhānekeaturāneingāwhareirotoiterimaheitiakeite16°Ctepaemahanatohariteoterūmanoho,eaikitetauiratuaritūponotangaewhakaahuatiaanairunga?
Whakamahiahetātaitangaheitautokoitōwhakautu.
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QUESTION TWO
(a) ThetablebelowshowstheprobabilitydistributionoftherandomvariableX.
x 0 1 2 3 4
P(X = x) 0.11 0.21 0.24 0.25 0.19
(i) E(X)=2.2.
CalculateVAR(X ).
(ii) TherandomvariableYhasVAR(Y)=1.5376.
VAR(X + Y )=5.5696.
AreXandYindependent?
Supportyouranswerwithappropriatestatisticalstatements.
(b) TheaveragetemperatureinaNewZealandlivingroomonawintereveningcanbemodelledbyanormaldistribution,withmean17.8°Candstandarddeviation2.1°C.
(i) Usingthismodel,betweenwhattwovalueswouldyouexpectthemiddle95%ofaveragetemperaturesforNewZealandlivingroomsonawintereveningtobe?
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(ii) DiscussONEfactorthatshouldbeconsideredwhenmodellingtheaveragetemperatureinaNewZealandlivingroomonawinterevening.
(iii) SupposethatfiveNewZealandhouseswereselectedatrandom,anditwasfoundthattheaveragetemperatureofthelivingroomonawintereveningwasbelow16°Cforfourofthesehouses.
Wouldfindingfourormorehousesoutoffivewithanaveragetemperatureofthelivingroombelow16°Cbeunlikelyundertheprobabilitydistributionmodeldescribedabove?
Supportyouranswerwithacalculation.
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Te Pāngarau me te Tauanga (Tauanga) 91586M, 2017
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TŪMAHI TUATORU
IkohiaetētahirangahaungāraraungamōtewhakamahiwaiirotoingākāingaiAotearoaheiāwhinaingākaunihera,ngātarikāwanatanga,mengākaiwhakaratowaikitewhakaurumaiingāwhakaritengamōtewhakamahitōtikaitewai.
Imuaiterangahau,kotewhakatautatahe4.7ngāwātohariteehīreretiaanateputungaparaeiatangataiAotearoairotoitētahiwā24haora.
(a) (i) MātewhakamahiitetauiratuaritangaPoisson,tātaihiahewhakatautatamōtetūponotangaheitiihoite5ngāwāehīreretiaanaetetangatateputungaparaitētahiwā24haora.
(ii) HomaikiaKOTAHItepūtakeheahaaiikoreetikapeatewhakamahiitētahituaritangaPoissonheiwhakatauiraitemahaongāhīrereputungaparamō tētahi wā 4 haora.
(b) Ikohiangāraraungamōtemahaongāwāihīreretiaeiatangatateputungaparairotoitētahiwā24haora.Kuawhakarāpopototiairaroitetūtohingāraraungamaiingātāngata200putanoaingākāinga84irotoiterangahau.
Te maha o ngā hīrere putunga para i tētahi wā 24 haora
0 1 2 3 4 5 6 7 8 9 10
Hautanga 0 0.01 0.1 0.17 0.26 0.14 0.12 0.11 0.05 0.01 0.03
(i) Tātaihiatetautohariteongāhīrereputungaparaiotiirotoitētahiwā24haoramōngātāngatairotoitēneirangahau.
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(ii) Hewhāiteitirawatehīrereputungaparaatenuingaongātāngatairotoitēneirangahauitētahiwā24haora?
Whakamahiahetātaitangaheitautokoitōwhakautu.
(iii) Ewhakaatuanatekauwhatairaroitetuaritangawhakamātautau(ngāpaekauruku)metētahituaritangaPoissonoteλ=4.7(tetauiratuaritangaewhakaaturiaanakitepango).
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Number of toilet flushes during a 24-hour period
Prop
ortio
n
2 3 4 5 6 7 8 9 100
0.05
0.10
0.15
0.20
0.25
0.30
MatapakitiakiaRUAngāpūtakeikoreaipeatetuaritangaPoissonoteλ=4.7itetauirapaimōtemahaongāhīrereputungaparamōtētahiwā24haora.
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Hautanga
Temahaongāhīrereputungaparaitētahiwā24haora
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QUESTION THREE
AstudycollecteddataonwaterusewithinNewZealandhomesforthepurposeofassistingcouncils,governmentagencies,andwatersupplierstointroducewaterefficiencymeasures.
Priortothestudy,itwasestimatedthateachpersoninNewZealandflushesthetoiletonaverage4.7timesper24-hourperiod.
(a) (i) UsingaPoissondistributionmodel,calculateanestimatefortheprobabilitythatapersonflushesthetoiletlessthanfivetimesinany24-hourperiod.
(ii) GiveONEreasonwhyitmaynotbeappropriatetouseaPoissondistributiontomodelthenumberoftoiletflushesforany 4-hour period.
(b) Datawascollectedonthenumberoftimeseachpersonflushedthetoiletduringa24-hourperiod.Thedatafrom200peoplefromacross84homesinthestudyissummarisedinthetablebelow.
Number of toilet flushes during 24-hour period
0 1 2 3 4 5 6 7 8 9 10
Proportion 0 0.01 0.1 0.17 0.26 0.14 0.12 0.11 0.05 0.01 0.03
(i) Calculatethemeannumberoftoiletflushesmadeper24-hourperiodforpeopleinthisstudy.
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(ii) Didmostpeopleinthisstudyflushthetoiletatleastfourtimesduringa24-hourperiod?
Supportyouranswerwithacalculation.
(iii) Thegraphbelowshowstheexperimentaldistribution(shadedbars)andaPoissondistributionwithλ=4.7(themodeldistributionshowninblack).
0 1
Number of toilet flushes during a 24-hour period
Prop
ortio
n
2 3 4 5 6 7 8 9 100
0.05
0.10
0.15
0.20
0.25
0.30
DiscussTWOreasonswhyaPoissondistributionwithλ=4.7maynotbeagoodmodelforthenumberoftoiletflushesforany24-hourperiod.
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2.
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He whārangi anō ki te hiahiatia.Tuhia te (ngā) tau tūmahi mēnā e tika ana.
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QUESTION NUMBER
Extra paper if required.Write the question number(s) if applicable.
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Level 3 Mathematics and Statistics (Statistics), 2017
91586 Apply probability distributions in solving problems
9.30 a.m. Monday 27 November 2017 Credits: Four
Achievement Achievement with Merit Achievement with ExcellenceApply probability distributions in solving problems.
Apply probability distributions, using relational thinking, in solving problems.
Apply probability distributions, using extended abstract thinking, in solving problems.
Check that the National Student Number (NSN) on your admission slip is the same as the number at the top of this page.
You should attempt ALL the questions in this booklet.
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YOU MUST HAND THIS BOOKLET TO THE SUPERVISOR AT THE END OF THE EXAMINATION.
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