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RedesignedSATMathPreparationTableofRedesignedSATMathPreparation AlignedwithCommonCore ComparisonwiththeCurrentSAT–NumberofQuestions& ComparisonwiththeCurrentSAT–Test The Zeroisan Zerocannotbe Positiveandnegative EvenandOdd Defined Distinct 1isnota Usingprimefactorizationtofindnumberof mberinan Prime Factorsand Factorsinword Commonmultipleword TheNumber Midpointonnumber Numberlinemidpointproblemcombinedwithexponential Round Digitsafter Sumof Findingnumberswithinarangeof PlaceValuewith Powerof Arithmeticofcomplex Orderof Ratios,proportionsand Confusingword SolutionConcentration Directly Combined SetsandVenn Combinationand Section HeartofAlgebra–Calculator CB-EX-1(identifymathematicalnotationforaninequalitytorepresentareal-world CB-EX-2(interpretthemeaningoftheslopeofthelineofbestfitinthecontext CB-EX-3(createalinearexpressiontorepresentareal-world CB-EX-4(convertcompoundinequalityintoadifferentformatandfinda Ex- CB-EX-5(interpretanexpressionorequationthatmodelsareal-world CB-EX-6(createafunctiontorepresentareal-world CB-EX-7(createasystemoflinearequationstorepresentareal-world CB-EX-8(constructalinearequationtorepresentareal-world CB-EX-9(understandtherelationshipbetweenanequationintwovariablesandits HeartofAlgebra–CalculatorNot CB-EX-1(makeaconnectionbetweenthegraphicalformandanumerical CB-EX-2(interprettheslopeofanequationinrelationtothereal-worldsituationit CB-EX-3(solvegebraicequationinone CB-EX-4(solveasystemoflinear CB-EX-5(usealgebraicoperationstodeterminethevalueofanewalgebraic Ex- CB-EX-6(solvingsystemsoflinearequationswithno ysisandProblemSolving–Calculator CB-EX-1RelationshipbetweenSampleSizeandSubjectSelectiononMarginof MarginofErrorandSample Sampleand Parameterand FourLevelsof Mean,Mode,Median,RangeandFrequency Deviation,VarianceandStander CB-EX-2(interpretinformationfromadata CB-EX-3(usethelineofbestfittomakea IdentifyingCorrelation IdentifyingCorrelation FindingLeanerRegressionandModelingtheData1(UsingTi FindingLinearRegressionandModelingtheData2(UsingTi CB-EX-4(determinethespecificrelationshipbetweentwocategorical CB-EX-5(retrieveinformationfromatabletoformorcomparerelevant CB-EX-6(extrapolatefromarandomsampletoestimateapopulation CB-EX-7(evaluatethemeansfortwoseparatepopulationstodeterminethe CB-EX-8(evaluatewhethertheresultscanbegeneralizedtothestudy CB-EX-9(interprettheslopeofthelineofbestfitastheaverage CB-EX-10(synthesizegraphicalinformationanddeterminewhatinformationis CB-EX-11(usetheunitrateandthe CB-EX-12(usealinearequationtodeterminetheconversion DB-EX-13(determineameaningfulvalueinthecontextofthe PassporttoAdvancedMath-Calculator CB-EX-2(identifythecorrectmathematicalnotationforanexponential CB-EX-3(manipulateoneequationforusein CB-EX-4(understandthezerosofapolynomial CB-EX-5(transformagivenexpressionfromimpropertoproperrational PassporttoAdvancedMath-CalculatorNot CB-EX-1(solveaquadratic CB-EX- (completeoperationswithmultiple CB-EX-3(polynomial CB-EX-4(fluencywithpropertiesof CB-EX-5(quadraticstandardform CB-EX-6(interpretanequationthatmodelsareal-world CB-EX-1(understandmathematicnotationandgeometric CB-EX-2(physicalconceptswithgeometric CB-EX-3(useofpropertiesof AdditionalTopic-CalculatorNot CB-EX-1(complexnumber CB-EX-2(radianmeasureandtrigonometric DegreeandRadian TrigonometricFunctions–Sine,Cosine,Tangent,Cosecant,Secantand AllSeniorsTake TrigonometricIdentities Reciprocal Quotient Cofunction Pythagorean CosineAddition/Subtraction DoubleAngle Parity CB-EX-3(propertiesofcirclesandparallellinesin CB-EX-4(radianmeasureandtrigonometric CB-EX-5(theequationofthe Math AlignedwithCommonCoreComparisonwiththeCurrentSAT–NumberofQuestions&ComparisonComparisonwiththeCurrentSAT–TestTestTheCategorizingthefollowing(1) (2)-5(3)5

(4) 7(6) (7)- (8)73.874(9)7

(10)ZeroisanForhowmanyintegersnis(2n1)(3n11)anegativeZerocannotbeIf(P3) (P5)(P

0,Whatisthevalueof030and0andPositiveandnegativeIfrs2t3u30andu0,whichofthefollowingmustberturtrtEvenandOddeven+even=even even×even=evenodd+odd=even odd×odd=oddodd+even= odd×even=Ifexactlytwoofthethreeintegersa,b,andcareodd,whichofthefollowingmustbeaca(bIIIIIIIandIIDefinedAnumberiscalled“even-odd”ifitishalfwaybetweenanevenintegerandanoddinteger.Ifxisaneven-oddnumber,whichofthefollowingmustbetrue?2xisan2xiseven-xishalfwaybetweentwoeven(A)I(B)II(C)III(D)I,IIandIIIAcleverintegerisdefinedasanintegerthatisgreaterthan20,lessthan100,andsuchthatthesumofitsdigitsis9.Whatfractionofallcleaverintegersisdivisibleby27?(A)8(B)4(C)8(D)2DistinctxyyxIntheadditionproblemabove,xandyaredistinctpositiveintegers.Howmanydifferentintegervaluesofxarepossible?(A)(B)(C)(D)1isnotapriHowmanyintegersgreaterthan20andlessthan30areeachtheproductofexactlytwodifferentnumbers,bothofwhichareprime?UsingprimefactorizationtofindnumberofIfN4p2q,wherepandqaredistinctprimbers,andnot2,howmanyfactorsdoesthenumberNhave?Primberinan90n23pIfnandparepositiveintegersintheequationabove,whatisonepossiblevalueofnpPrimeIfmisthegreatestprimefactorof38andnisthegreatestprimefactorof100.Whatisthevaluem7FactorsandFactorsinwordLeta“prd”numberbedefinedasoneinwhichtheproductofthepositivedivisorsofthenumber,notincludingthenumberitself,isgreaterthanthenumber.Whichofthefollowingisaprdnumber?8CommonmultiplewordHowmanypositiveintegerslessthan1,000aremultiplesof5andareequalto3timesanevenHowmanypositiveintegerslessthan1000aremultiplesof3ormultiplesofTheintegernisequaltok2forsomeintegerk.Ifnisdivisibleby24andby10,whatisthesmallestpositivevalueofn?IfSisthesetofprimbersbetween1and20andTisthesetofallpositivemultiplesof3or5,howmanynumbersappearinbothSandTTheNumberMidpointonnumberOnthenumberlineabove,thetickmarksareequallyspaced.Whichoftheletteredpointsrepresents(A)(B)(C)(D)NumberlinemidpointproblemcombinedwithexponentialOnthenumberlineabove,pointsBisthemidpointofAC.IfKispositive,whatisthevalueofRoundWhen1.783isroundedtothenearestwholenumber,theresultishowmuchgreaterthanwhen1.783isroundedtothenearesttenth?DigitsafterWhenxisexpressedasadecimal,thehundredthsdigitis8,whatisthegreatestpossiblevalueof1xSumofnTheintegernaboveisformedbywritingconsecutiveintegers,startingwith1001andendingwith1020.Whatisthesumofthedigitsofn?FindingnumberswithinarangeofIntheinteger3589thedigitsaredifferentandincreasefromlefttoright.Howmanyintegersbetween4,000and5,000havedigitsthatarealldifferentandthatincreaseformlefttoright?PlaceValuewithIfnisatwo-digitnumberwhoseunitsdigitis4timesitstensdigit,whichofthefollowingstatementsmustbetrue?nisamultipleofnisamultipleofnisamultipleofnislessthanComplexNumbers(Redesigned*RedesignedSATSampleProblem–AdditionalTopic–CalculatorNotPermittedWhichofthefollowingisequalto(142i)(712i)?PowerofSimplifythe 2.i4343.i194.i1275.

7.(40)(12ArithmeticofcomplexPerformeachoperation.Writeyouranswersinabi(45i)(9 2.(87i)(2 3.(23i)(4 4.(73i5)(42i552i3i (7352i3i3Findthevaluesofxandyif(3x2y)(5x7y)i13

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264OrderofThesquareofxisequalto4timesthesquareofy.Ifxis1morethantwicey,whatisthevalueofx2412Thesumoftwonumbersthatdifferby1ist.Intermsoft,whatisthevalueofthegreaterofthetwot1t2t22t2Twicethesumoftwoconsecutiveintegersisklessthanfivetimesthesmallerinteger,wherekisapositiveinteger.Whatisthelargerinteger,intermsofk?kkk2kReminderWhenthepositiveintegerxisdividedby5,theremainderis3.Whatistheremainderwhenx19isdividedby5?Thenumbernisa2-digitnumber.Whennisdividedby10,theremainderis9,andwhennisdividedby9,theremainderis8.Whatisthevalueofn?When15isdividedbythepositiveintegerK,theremainderis3.ForhowmanydifferentvaluesofKisthistrue?(A)(B)(C)(D)Exponential*RedesignedSATSampleProblem–HeartofAlgebra–CalculatorIf

2x,wherea>0andx>0,whichofthefollowingequationsgivesaintermsofxxaxaxxx22Ifx3y,whatdoesx4equalintermsofyIf(110n)(7105)7.001105,whatisthevalueofIf3k3k3k(27)5,whatisthevalueof96Forallpositiveintegerswandy,wherew>y,lettheoperation⌫bedefinedbyw⌫ymanypositiveintegerswisw⌫1equalto4?234Morethan

2wy.For2w Evaluate(43)(26)(32 (22)(32Ifxandyarepositiveintegers,whichofthefollowingisequivalentto(2x)3y2y(x3xy)(2x)y[(2x)2y(2x)y[(2x)3Ratios,proportionsandConfusingwordAmeasuringcupcontains1ofacupoforangejuice.Itisthenfilledtothe1-cupmarkwitha5thatcontainsequalamountsoforange,grfruit,andpineapplejuices.Whatfractionofthefinalmixtureisorangejuice?Two ,xandy,havethesamecapacity.Theamountofoil xis1ofitscapacity,and2amountofoilinyis1200gallonslessthanitscapacity.Ifthereare7800gallonsofoilinthetwocombined,whatisthecapacity,ingallons,ofx?Inacertainclass,4ofthestudentsareboys,andtheratioofthestudentsolderthanorequalto7yearstothestudentslessthan10yearsoldis2:3.If2ofthegirlsarelessthan10yearsold,3fractionoftheboysareolderthanorequalto109923SolutionConcentration20gramsofsolutionAhas10%ofalcoholbymassand15gramsofsolutionBhas20%ofalcoholbymass.If10gramsofthesolutionAisaddedto10gramsofthesolutionB,whatisthepercentofalcoholinthemixture?DirectlyIfa,b, c,andfarefournonzeronumbers,thenallofthefollowingproportionsareequivalenta fb a af Arecipeformaking20pepperonipizzapiesrequires32poundsofflour,5poundsofbakingpowder,and4poundsofpepperoni.Iftheproportionsinthisrecipearetobeusedtomake15pepperonipizzapies,howmanypoundsofpepperoniwillbeneeded?XYab5aInthetableabove,yisdirectlyproportionaltox.Whichofthefollowingisthevalueof345Tomakeanorangedye,5partsofreddyearemixedwith3partsofyellowdye.Tomakeagreendye,4partsofbluedyearemixedwith2partsofyellowdye.Ifequalamountofgreenandorangearemixed,whatfractionofthenewmixtureisyellowdye?InverselyAcertainjobcanbedonein20hoursby4people.Howmanypeopleareneededtodothesamejobin10hours?(A)(B)(C)(D)Ifx0andxininverselyproportionaltoy.,whichofthefollowingisdirectlyproportional 11yyIfmmencandoajobinddays,thenmrmencandothejobdrdr mdm

Forthefunctionf,f(x)isinverselyproportionaltox.Iff(k)a,whatisthevaluea3

f(k)CombinedAfarmercanplowafieldinkdays.Howmanydayswillittaketwofarmersworkingatthesameratetoplowafieldtwotimeslarger?kAsales’scommissionisKpercentofthesellingpriceofacar.Whichofthefollowingrepresentsthecommission,indollars,on2carsthatsoldfor$14,000each?14,Thereare75morewomenthanmenenrolledinLindenCollege.Iftherearenmenenrolledthen,intermsofn,whatpercentofthoseenrolledaremen? n 2n100nn100n2nIfqandrarepositivenumbers,whatpercentof(q+1)is 100r(qq1100(qr100rqToarriveontime,ashipneeds5hourstocompeteavoyage.Iftheshipmustarrivein4hours,bywhatpercentmustthespeedoftheshipbeincreased?Successivediscountsof10%and20%areequivalenttoasinglediscountSetsandVenn

Inthefiguretotheright,circularregionPrepresentsshirtswithpockets,circularregionQrepresentsshirtswithbuttons,andcircularregionRrepresentsshirtswithcollars.Whatisrepresentedbytheshadedregion?Shirtswithpockets,buttons,andShirtswithpocketsandbuttons,butwithoutShirtswithpocketsandbuttonspossiblywithShirtswithpocketsandcollars(somepossiblywithbuttons)SetScontainsofnintegers,andthedifferencebetweenthegreatestintegerinSandtheleastintegerinSis550.Anewsetofnintegers,setT,isformedbymultiplyingeachintegerinSby4andthenadding5totheproduct.WhatisthedifferencebetweenthegreatestintegerinTandtheleastintegerinT?Inanassortmentofcereals,23typescontainoatsand25typescontainrice.Someofthesecerealscontainbothoatsandrice.If16cerealsinthisassortmentcontainoatsbutnotrice,howmanycerealscontainricebutnotoats?Eachstudentinagroupof30studentsstudiesGerman,Italian,orboth.ThetotalnumberofstudentsstudyingGermanisthreemorethanthetotalnumberofstudentsstudyingItalian.Ifthenumberofstudentsthatstudybothsubjectsisthesameasthenumberofstudentsthatstudyexactlyonesubject,howmanystudentsinthegroupstudyonlyItalian?Eachtermofacertainsequenceisgreaterthanthetermbeforeit.Thedifferencebetweenanytwoconsecutivetermsinthesequenceisalwaysthesamenumber.Ifthethirdandsixthtermsofthesequenceare17and77,respectively,whatistheeighthterm?y,2y7,yIntheincreasingsequenceabove,thetermisyandthedifferencebetweenanytwoconsecutivetermsis3.Whatisthevalueofthefourthterminthesequence?(A)(B)(C)(D)2.2.PAGE2.2.PAGE6.3Ex-ThetermofsequencePis2,andeachtermaftertheis2timestheprecedingterm.ThetermofsequenceTis10,andeachtermaftertheis10morethantheprecedingtherm.whatistheleastvalueofnsuchthatthenthtermofsequencePisgreaterthanthenthtermofsequenceT?(A)(B)(C)(D)Thenthtermofasequenceisgivenbyanank,whereaandkareconstants.Ifthe5thtermis20andthe10thtermis30inthesequence,whatisthevalueofa1?a,ar,ar2,Inthesequenceabove,thetermisaandeachtermaftertheisobtainedbymultiplyingtheprecedingtermbyr.Ifthethirdandfifthtermsinthesequenceare2and8,whatisthevalueofthe7thAcompanysellsboxesofballoonsinwhichtheballoonsarered,green,orblue.Luannaboxofballoonsinwhich3

ofthemwerered.Iftherewerehalfasmanygreenballoonsintheboxredonesand18balloonswereblue,howmanyballoonswereintheIfjischosenatrandomfromtheset{4,5,6}andkischosenatrandomfromtheset{10,11,12},whatistheprobabilitythattheproductofjandkisdivisibleby5?2.2.PAGE72.2.PAGE7.3Ex-Abagcontains3redmarblesand6blackmarbles.Whatistheprobabilitythatyouselecttworedmarblesifyoureachinthebagandrandomlygrabtwomarbleswithoutreplacement?(A)9 Theintegers1through6appearonthesixfacesofacube,oneoneachface.Ifthreesuchcubesarerolled,whatistheprobabilitythatthesumofthenumbersonthetopfacesis17or18? Carolhas5scarvesand5sweaters,andeachscarfmatchesadifferentsweater.Ifshechoosesoneofthesescarvesatrandom,whatistheprobabilitythattheywillnotmatch?CombinationandForaclassring,eachseniorcanchoosefrom4typesofstonesand3typesofmetals.Howmanycombinationsofastoneandametalarethere?78Asshownabove,acertaindesignistobepaintedusing2differentcolors.If5differentcolorsareavailableforthedesign,howmanydifferentlypainteddesignsarepossible?Meredithhasaredhat,abluehat,andawhitehat.Shealsohasthreesweaters—onered,oneblue,andonewhite—andthreepairsofjeans—onered,oneblue,andonewhite.Meredithwantstowearared,white,andblueoutfitconsistingofonehat,onesweater,andonepairofjeans.Howmanydifferentpossibilitiesdoesshehave?369Aboxcontainswoodbeads,redglassbeads,andblueglassbeads.Thenumberofglassbeadsis4timesthenumberofwoodbeads.Ifonebeadistobechosenatrandomfromthebox,theprobabilitythataredglassbeadwillbechosenis3timestheprobabilitythatablueglassbeadwillbechosen.Ifthereare12redglassbeadsinthebox,whatisthetotalnumberofbeadsinthebox?Ex-TheAcmePlumbingCompanywillsendateamof3plumberstoworkonacertainjob.Thecompanyhas4experiencedplumbersand4trainees.Ifateamconsistsof1experiencedplumberand2trainees,howmanydifferentsuchteamsarepossible?Any2pointsdeterminealine.Ifthereare6pointsinaplane,no3ofwhichlieonthesameline,howmanylinesaredeterminedbypairsofthese6points?Ifthe5cardsshownaboveareplacedinarowsothatisneverateitherend.Howmanydifferentarrangementsarepossible?Thefigureaboverepresentsfourofficesthatwillbeassignedrandomlytofouremployees,oneemployeeperoffice.IfKarenandTinaaretwoofthefouremployees,whatistheprobabilitythateachwillbeassignedanofficeindicatedwithanX?1116Ex-ThelettersA,B,C,D,andEaretobearrangedintheboxesabove,oneineachbox,inthefollowingway.AmustbebetweenCandD,BmustbenexttoE,andCcannotbeinthe orfifthpositions.Howmanydifferentarrangementsoftheselettersarepossible?0Ex-Atanamusementpark,5childrenwillbeassignedtorideinthe5carsbehindtheengineofthetrainshownabove,onechildpercar.HowmanydifferentassignmentsofthechildrentothecarsareSectionHeartofAlgebra–CalculatorCB-EX-1(identifymathematicalnotationforaninequalitytorepresentareal-world mendeddailycalciumintakefora20-year-oldis1,000milligrams(mg).Onecupofmilkcontains299mgofcalciumandonecupofjuicecontains261mgofcalcium.Whichofthefollowinginequalitiesrepresentsthepossiblenumberofcupsofmilkmandcupsofjuiceja20-year-oldcoulddrinkinadaytomeetorexceedthe mendeddailycalciumintakefromthesedrinksalone?299m261j299m261j Ex-ThevelocityofanobjectfireddirectlyupwardisgivenbyV=80–32t,wheretisinseconds.Whenwillthevelocitybebetween32and64feetpersecond?1.5t0.5t7t5tAcompanymanufacturescarparts.Asisthecasewithanysystemofmassproduction,smallerrorsinproductionofeverypartoccur.Tomakeviablecarparts,thecompanymustmakesuretheunavoidableerrorsoccuronlywithinaspecificrange.Thecompanyknowsthataparticularparttheymanufacturewillnotworkifitweighslessthan98%ofitsweightormorethan102%ofitsweight.Iftheweightofthispieceis21.5grams,whatistherangeofweightsthepartmustfallwithinforittofunction?Atheatercompanyisauditioningforactorstoportraytheleadingcharacterinanewplay.Thecompanyislookingforactorsbetweentheagesof20and40(inclusive).Whichofthefollowinginequalitiescanbeusedtodeterminewhetheranactorofageaiseligibletoauditionforthepart?a10a20a30a30Ex-loyneedstocontainbetween46%copperand50%copper.Findtheleastandgreatestamountof60%copperalloythatshouldbemixedwitha40%copperalloyinordertoendupwiththirtypoundsofloycontaininglowablepercentageofcopper.9x12x15x21xEx-Youwanttoinvest$30,000.Partofthiswillbeinvestedinastable5%-simple-interestrateaccount.Theremainderwillbe"invested"inyourfather'sbusiness,andhesaysthatpayyoubackwith7%interest.Yourfatherknowsthatyou'remakingtheseinvestmentsinordertopayyourchild'scollegetuitionwiththeinterest e.Whatistheleastyoucan"invest"withyourfather,andstill(assuminghereallypaysyouback)getatleast$1900ininterest?CB-EX-2(interpretthemeaningoftheslopeofthelineofbestfitinthecontext metacarpalboneislocatedinthewrist.Thescatterplotbelowshowstherelationshipbetweenthelengthofthe metacarpalboneandheightfor9people.ThelineofbestfitisalsoWhichofthefollowingisthebestinterpretationoftheslopeofthelineofbestfitinthecontextofthisThepredictedheightincreaseincentimetersforone-centimeterincreaseinthemetacarpalThepredictedmetacarpalboneincreaseincentimetersforeverycentimeterincreaseThepredictedheightincentimetersofa witha metacarpalbonelengthof0Thepredicted metacarpalbonelengthincentimetersfora withaheightof0For12bottlesofshampooofvariousbrands,thecostandvolumeofeacharedisplayedinthescatterplotabove,andthelineofbestfitfordataisshown.Ofthefollowing,whichisclosesttotheaverage(arithmeticmean)costperounceforthe12bottles?Abiologyteachergraphedthelengthofafishovertime,andtheresultsareshownabove.IfLrepresentsthelengthofthefishinmillimetersandWrepresentsthenumberoftheweek,whichofthefollowingequationsbestdescribesthedatashown?ThescatterplotaboveshowsthenumberofmaleandfemalestudentsatCentralHighSchoolfrom1990to1999.Inwhichoneoftheyearsshownwastheabsolutevalueofthedifferencebetweenthenumbersofmaleandfemalestudentsgreatest?ThecountryoforiginisafunctionofthestudentThestudentnameisafunctionofthecountryofBothstatementsareNeitherstatementisDoug’sbiologyexperimentinvolvedtiming12hamstersinamaze.Eachhamsterreceivedatleastonepracticebeforebeingtimed.Thescatterplotaboveshowsthetimeeachhamstertooktocompletethemazeandthecorrespondingnumberofpracticesthateachhamsterreceived.bastedonthedata,whichofthefollowingfunctionsbestmodelstherelationshipbetweent,thenumberofsecondstocompletethemaze,andp,thenumberoft(p)t(p)t(p)44t(p)pJoannelovestoplayherfluteforthebirdsinthewoods.Shedecidedtoseeifplayingcertainnoteswouldattractdifferentnumbersofbirds,andshemadeatableshowingherresults.Whichofthesestatementsabouttherelationinthetablebelowaretrue?ThenumberofbirdsattractedisafunctionofthenoteThenoteplayedisafunctionofthenumberofbirdsBothstatementsareNeitherstatementisCB-EX-3(createalinearexpressiontorepresentareal-world*Aaronisstayingatahothatcharges$99.95pernightplustaxforaroom.Ataxof8%isappliedtotheroomrate,andanadditionalonetimeuntaxedfeeof$5.00ischargedbytheho.WhichofthefollowingrepresentsAaron’stotalcharge,indollars,forstayingxnights?Thecostofaephonecallusinglong-distancecarrierAis$1.00foranytimeuptoandincluding20minutesand$0.07perminutethereafter.Thecostusinglong-distancecarrierBis$0.06perminuteforanyamountoftime.Foracallthatlaststminutes,thecostusingcarrierAisthesameasthecostusingcarrierB.Iftisapositiveintegergreaterthan20,whatisthevalueoft?Howoldwasrsonexactly1yearagoifexactlyxyearsagothewasyyearsyx1xy1yx1yx1Duringasale,acustomercanbuyoneshirtforxdollars.EachadditionalshirtthecustomerbuysZdollarsthantheshirt.Forexample,thecostofthesecondshirtisx-zdollars.Whichofthefollowingrepresentsthecustomer’scost,indollars,fornshirtsboughtduringthissale?x(n1)(xxn(xn(xx(xnPhillipusedfourpiecesofmaskingt,each6incheslong,toputupeachofhisposters.Philiphada300-footrollofmaskingtwhenhestarted.Ifnotwaswasted,whichofthefollowingrepresentsthenumberoffeetofmaskingtthatwasleftontherollafterheputupnposters?(12inches=1foot)30030030012Duringaone-centsale,ashopperpaystheregular