math homework helper - sharpschool

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Homework Helper 1 Math Homework Helper Number and Operations in Base Ten MCC4.NBT.1 Recognize that in a multi‐digit whole number, a digit in one place represents ten times what it represents in the place to its right. MCC4.NBT.2 Read and write multi‐digit whole numbers using base‐ten numerals, number names, and expanded form. Compare two multi‐digit numbers based on meanings of the digits in each place, using >, =, and < symbols to record the results of the comparison. Base Ten refers to the numbering system in common use. Take a number like 475, base ten refers to the position, the 5 is in the one's place, the 7 is in the ten's place and the 4 is in the hundred's place. Each number is 10 times the value to the right of it, hence the term ‘base ten’. Base 10 blocks are often used in class to help students grasp number. Base ten blocks have ‘a unit’ to represent one, ‘a rod’ to represent ten and ‘a flat’ to represent 100. millions’ hundred thousands’ ten thousands’ thousands’ hundreds’ tens’ ones’ tenths’ hundredths’ 6, 4 7 2, 9 1 3. 5 8 Example:7 place: ten thousands’ place value: 70,000 Example:9 place: hundreds’ place value: 900 digit : number expanded form : to show a number as the sum of the value of its digits Example: 7,965 in expanded form is 7,000+900+60+5 Example: one thousand twelve in expanded form is 1,000 + 10 + 2 numeral : the usual way of writing a number Example: 234,908 Example: 400+20+2 is 422 Example: Fifteen is 15. number name : to show a number as word(s) Example: 14,009: the number name is fourteen thousand, nine Example: 23.09: the number name is twenty‐three and nine hundredths Example: 2.9: the number name is two and nine tenths Think: Place is a word (name) Value is a number (digits)

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Page 1: Math Homework Helper - SharpSchool

Homework Helper 1

MathHomeworkHelperNumberandOperationsinBaseTenMCC4.NBT.1Recognizethatinamulti‐digitwholenumber,adigitinoneplacerepresentstentimeswhatitrepresentsintheplacetoitsright.MCC4.NBT.2Readandwritemulti‐digitwholenumbersusingbase‐tennumerals,numbernames,andexpandedform.Comparetwomulti‐digitnumbersbasedonmeaningsofthedigitsineachplace,using>,=,and<symbolstorecordtheresultsofthecomparison.BaseTenreferstothenumberingsystemincommonuse.Takeanumberlike475,basetenreferstotheposition,the5isintheone'splace,the7isintheten'splaceandthe4isinthehundred'splace.Eachnumberis10timesthevaluetotherightofit,hencetheterm‘baseten’.Base10blocksareoftenusedinclasstohelpstudentsgraspnumber.Basetenblockshave‘aunit’torepresentone,‘arod’torepresenttenand‘aflat’torepresent100.

millions’

hundred

thousands’

ten

thousands’

thousands’

hundreds’

tens’

ones’

tenths’

hundredths’

6, 4 7 2, 9 1 3. 5 8

Example:7place:tenthousands’place value:70,000 Example:9place:hundreds’place value:900

digit:number

expandedform:toshowanumberasthesumofthevalueofitsdigits Example:7,965inexpandedformis7,000+900+60+5 Example:onethousandtwelveinexpandedformis1,000+10+2

numeral:theusualwayofwritinganumber Example:234,908 Example:400+20+2is422 Example:Fifteenis15.

numbername:toshowanumberasword(s) Example:14,009:thenumbernameisfourteenthousand,nine Example:23.09:thenumbernameistwenty‐threeandninehundredths Example:2.9:thenumbernameistwoandninetenths

Think:Placeisaword(name)Valueisanumber(digits)

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ComparingWholeNumbersSymbolsareusedtoshowhowthesizeofonenumbercomparestoanother.Thesesymbolsare<(lessthan),>(greaterthan),and=(equals).Forexample,since2issmallerthan4and4islargerthan2,wecanwrite:2<4,whichsaysthesameas4>2andofcourse,4=4.

• Tocomparetwowholenumbers,firstputtheminnumeralform.• Thenumberwithmoredigitsisgreaterthantheother.• Iftheyhavethesamenumberofdigits,comparethedigitsinthehighestplacevalueposition(theleftmostdigitofeachnumber).Theonehavingthelargerdigitisgreaterthantheother.

• Ifthosedigitsarethesame,comparethenextpairofdigits(lookatthenumberstotheright).

• Repeatthisuntilthepairofdigitsisdifferent.Thenumberwiththelargerdigitisgreaterthantheother.

Example:402hasmoredigitsthan42,so402>42.Example:402and412havethesamenumberofdigits.Wecomparetheleftmostdigitofeachnumber:4ineachcase.Movingtotheright,wecomparethenexttwonumbers:0and1.Sincezeroislessthanone,402islessthan412or402<412.

RoundingMCC4.NBT.3Useplacevalueunderstandingtoroundmulti‐digitwholenumberstoanyplace.

RuleOne.Determinewhatyourroundingdigitisandunderlineit.Thenlooktotherightsideofit.Ifthedigitis0,1,2,3,or4donotchangethedigityouunderlined.Alldigitsthatareontherighthandsideoftherequestedroundingdigitwillbecome0.RuleTwo.Determinewhatyourroundingdigitisandunderlineit.Thenlooktotherightofit.Ifthedigitis5,6,7,8,or9,yourunderlinednumberupbyone.Alldigitsthatareontherighthandsideoftherequestedroundingdigitwillbecome0.

roundingtothenearestwholenumber(theones’place) 1.25to1 45.8to46 23.398to23

roundingtothenearestten 21to20 95to100 441 to440 1,125to1,130

roundingtothenearesthundred 236 to200 754 to800 1,992to2,000 1,232to1,200

roundingtothenearestthousand 2,363to2,000 7,541to8,000 14,227to14,000

roundingtothenearestmillion 2,908,674to3,000,000 14,643,960to15,000,000

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EstimationMCC4.OA.3Assessthereasonablenessofanswersusingmentalcomputationandestimationstrategiesincludingrounding.

estimatethesum:roundthenumbers,thenadd23 20 345 300 9,1229,000+89 +90 +496 +500 +5,631+6,000110 800 15,000estimatethedifference:roundthenumbers,thensubtract45 50 7457009,129 9,000‐21 ­20 ‐496 ­500 ‐5,631­6,00030 200 3,000estimatetheproduct:roundthenumbersandmultiply78 80 67 70 254 300x5x5 x18 x20 x349x300400 1,400 90,000estimatethequotient:roundthenumbersanddivide61÷2= 891÷32=60÷2=30 900÷30=30

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MultiplicationMCC4.NBT.5Multiplyawholenumberofuptofourdigitsbyaone‐digitnumber,andmultiplytwotwo‐digitnumbers,usingstrategiesbasedonplacevalueandthepropertiesofoperations.Illustrateandexplainthecalculationbyusingequations,rectanglearrays,and/orareamodels.PropertiesofMultiplicationcommutativepropertyofmultiplication:theorderofthefactorsdoesnotchangeaproduct. Example:2 4=4 28=8

associativepropertyofmultiplication:thewayfactorsaregroupeddoesnotchangetheproduct. Example:(2 3) 4=2 (3 4) 6 4=2 12 24=24

multiplicativeidentityproperty:anynumbermultipliedbyoneremainsthesamenumber. Example:5 1=5or1×5=5

distributivepropertyofmultiplication:multiplyingasumbyanumberisthesameasmultiplyingeachaddendbythenumberandthenaddingtheproblem. Example:2 (3+4)=(2 3)+(2 4) 2 7=6+814=14 Example:432x4=(400x4)+(30x4)+(2x4) 1,728=1,600+120+81,728=1,728 zeropropertyofmultiplication:anynumbermultipliedbyzerowillresultintheproductofzero Example:5 0=0or0×5=0

MultiplicationAlgorithm +4+2+1+1+312 23 432723 2125 x2 x7x2x6 x12x97 24 1618644,338 42175+210+2250 2522,425

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RectangleArrays

AreaModels

DivisionMCC4.NBT.6Findwhole‐numberquotientsandremainderswithuptofour‐digitdividendsandone‐digitdivisors,usingstrategiesbasedonplacevalue,thepropertiesofoperations,and/ortherelationshipbetweenmultiplicationanddivision.Illustrateandexplainthecalculationbyusingequations,rectangulararrays,and/orareamodels.

DivisionAlgorithm

9R292R8928R71049 ‐81‐81‐81‐82292503 ‐21‐18‐087939‐72‐32772 ‐72 0

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DivisibilityRules(forwholenumbers)Anumberisdivisibleby2ifthedigitinitsones’positioniseven,(either0,2,4,6,or8).Anumberisdivisibleby3ifthesumofallitsdigitsisdivisibleby3.Anumberisdivisibleby4ifthenumberformedbythelasttwodigitsisdivisibleby4.Anumberisdivisibleby5ifthedigitinitsones’positionis0or5.Anumberisdivisibleby6ifitisanevennumberanddivisibleby3.Anumberisdivisibleby8ifthenumberformedbythelastthreedigitsisdivisibleby8.Anumberisdivisibleby9ifthesumofallitsdigitsisdivisibleby9.Anumberisdivisibleby10ifthedigitinisones’placeiszero.

GeometryMCC4.G.1Drawpoints,lines,linesegments,rays,angles(acute,right,obtuse),andperpendicularandparallellines.Identifytheseintwo‐dimensionalobjects.MCC4.G.2Classifytwo‐dimensionalfiguresbasedonthepresenceorabsenceofparallelorperpendicularlines,orthepresenceorabsenceofanglesofaspecifiedsize.Recognizerighttrianglesasacategory,andidentifyrighttriangles.MCC4.G.3Recognizealineofsymmetryforatwo‐dimensionalfigureasalineacrossthefiguresuchthatthefigurecanbefoldedalongthelineintomatchingparts.Identifyline‐symmetricfiguresanddrawlinesofsymmetry.MCC4.MD.3Applytheareaandperimeterformulasforrectanglesinrealworldandmathematicalproblems.

intersectinglines:twolinesthatcrossparallellines:linesthatneverintersectperpendicularlines:linesthatintersectandformrightanglesarea:tofigurearea,multiplythelengthbythewidth.5ft5ft×8ft=40squarefeet8ftarea=40squarefeet

8in.×8in.=64squareinches8in.area=64squareinches*Squarehasallequalsides.Sometimesonlyonelinesegmentislabeledwiththemeasurement.

9miles� area=72squaremiles�×9mi=72squaremi. 72sqmi.÷9mi.=8mi.

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perimeter:tofigureperimeter,alladdthesides.�+3m+4m+3m+4m=17m3m3m+4m+3m+4m=14m5ft5+5+8+8=26feet�4m17m‐14m=3mperimeter=26feetP=17m�=3m 8ft4m3m

Angle:tworaysthatshareacommonendpoint.

AcuteAngleAnglethatislessthan90°.

RightAngleAnglethatis90°.

ObtuseAngleAnglethatismorethan90°.

Triangle:three‐sidedpolygonwhoseangles’sumare180°.RightTriangle

onerightangle.perpendicularlines

AcuteTriangleallacuteangles.

ObtuseTriangleoneobtuseangle.

EquilateralTriangle

Allthreeequallengthsides

IsoscelesTriangleTwoequallengthsides

ScaleneTriangleNosidesofequallength

60°+90°+�=180° 60°60°180°+90°‐150°� 150°30°y=30°

Quadrilateralsfour‐sidedpolygon

TrapezoidParallelogramonesetofparallellines twosetsofparallellinesoppositesidesareequal

RhombusRectangletwosetsofparallellinestwosetsofparallellines

allsidesequal oppositesidesareequal allrightangles

(perpendicularlines)Square

twosetsofparallellinesallsidesareequalallrightangles(perpendicularlines)

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Symmetry• Lineofsymmetryisalinethatdividesafigureintotwocongruentparts,eachofwhichisthemirrorimageoftheother.

• Whenthefigurehavingalineofsymmetryisfoldedalongthelineofsymmetry,thetwopartsshouldmatchup.

AngleMeasurementMCC4.MD.5Recognizeanglesasgeometricshapesthatareformedwherevertworaysshareacommonendpoint,andunderstandconceptsofanglemeasurement:

a) Anangleismeasuredwithreferencetoacirclewithitscenteratthecommonendpointoftherays,byconsideringthefractionofthecirclearcbetweenthepointswherethetworaysintersectthecircle.

b) Ananglethatturnsthrough1/360ofacircleiscalleda“one‐degreeangle”,andcanbeusedtomeasureangles.

MCC4.MD.6Measureanglesinwhole‐numberdegreesusingaprotractor.Sketchanglesofspecifiedmeasure.

Protractor:tooltomeasureangles.

ToMeasureanAngle• Findthecenterholeonthestraightedgeoftheprotractor.• Placetheholeoverthevertex,orpoint,oftheangleyouwishtomeasure.• Lineupthezeroonthestraightedgeoftheprotractorwithoneofthesidesoftheangle.

• Findthepointwherethesecondsideoftheanglecrossesthecurvededgeoftheprotractor.Readthenumberthatiswrittenontheprotractoratthispoint.Thisisthemeasureoftheangleindegrees.

ToConstructanAngle• Usethestraightedgeoftheprotractortodrawastraightline.Thislinewillformonesideofyourangle.

• Findthecenterholeonthestraightedgeoftheprotractor.Placetheholeoveroneendpointofthelineyouhavedrawn.(continuedonnextpage)

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• Lineupthezeroonthestraightedgeoftheprotractorwiththeline.• Makeamarkatthenumberonthecurvededgeoftheprotractorthatcorrespondstothedesiredmeasureofyourangle.Forexample,markat90fora90‐degreeangle.

• Usethestraightedgeoftheprotractortoconnectthemarktotheendpointofthefirstline,forminganangle.

MCC4.MD.7Recognizeanglemeasureasadditive.Whenanangleisdecomposedintonon‐overlappingparts,theanglemeasureofthewholeisthesumoftheanglemeasuresoftheparts.Solveadditionandsubtractionproblemstofindunknownanglesonadiagraminrealworldandmathematicalproblems.

CircleVocabularyCenter:thepointdirectlyinthemiddleofthecircle.Radius:alinesegmentthattravelsfromthecenterofthecircletotheoutsiderim.RadiusDiameter:alinesegmentthattravelscompletelyacrossthecirclepassingthroughthecenter.Diameter

Benchmarkangles:90°isarightangle

180°isastraightangle

MeasurementMCC4.MD.1Knowrelativesizesofmeasurementunitswithinonesystemofunitsincludingkm,m,cm;lb,oz;l,ml;hr,min,sec.Withinasinglesystemofmeasurement,expressmeasurementsinalargerunitintermsofasmallerunit.MCC4.MD.2Usethefouroperationstosolvewordproblemsinvolvingdistances,intervalsoftime,liquidvolumes,massesofobjects,andmoney,includingproblemsinvolvingsimplefractionsordecimals,andproblemsthatrequireexpressingmeasurementsgiveninalargerunitintermsofasmallerunit.

metricunits customaryunitsweightmass

1kilogram(kg)=1,000grams(g) 1pound(lb)=16ounces(oz)

lengthdistance

1kilometer(km)=1,000meter(m)1meter(m)=100centimeters(cm)

1yard(yd)=3feet(ft)or36in.1foot(ft)=12inches(in.)

capacityliquidvolume

1liter(l)=1,000millimeters(ml) 1gallon(gal)=4quarts(qt)1quart(qt)=2pints(pt)1pint(pt)=2cups(c)

time1hour=60minutes1minute=60seconds

Toconvertalargerunittoasmallerunitofmeasure,youmultiply.Forexampleyouchange5meters(largeunit)tocentimeters(smallerunit),thereare100centimetersinonemeter.Multiply5×100=500cm.Therefore5m=500cm.

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Sometimesconversionsaremulti‐stepproblemssuchasconverting2gallonstopints.First,multiply2by4,whichis8quarts;thenmultiple8quartsby2whichequals16pints.

DataMCC.MD.4Makealineplottodisplayadatasetofmeasurementsinfractionsofaunit(12,14,18).Solveproblemsinvolvingadditionandsubtractionoffractionsbyusinginformationpresentedinlineplots.Alineplotisagraphthatshowsfrequencyofdataalonganumberline.Itisbesttousealineplotwhencomparingfewerthan25numbers.Itisaquick,simplewaytoorganizedata.Alineplotconsistsofahorizontalnumberline,onwhicheachvalueofasetisdenotedbyanxoverthecorrespondingvalueonthenumberline.Thenumberofx'saboveeachscoreindicateshowmanytimeseachvalueoccurredinthedataset.dataset:

18,18,38,38,38,48,58,68,68,68,68,78,88,88,98,128,128

TheLengthofJamie’sEarthworms

NumberandOperations­FractionsGrade4expectationsinthisdomainarelimitedtofractionswithdenominatorsof2,3,4,5,6,8,10,12,and100.

Extendunderstandingoffractionequivalenceandordering.

MCC4.NF.1Explainwhyafraction��isequivalenttoafraction(��) (��) byusingvisualfractionmodels,withattentiontohowthenumberandsizeofthepartsdiffereventhoughthetwofractionsthemselvesarethesamesize.Usethisprincipletorecognizeandgenerateequivalentfractions.Equivalentfractionscanbecreatedbymultiplying(ordividing)boththenumeratoranddenominatorbythesamenumber.Wecandothisbecause,ifyoumultiplyboththenumeratoranddenominatorofafractionbythesamenumber,thefractionremainsunchangedinvalue.Inthemodelbelow,youcouldgetthefraction46bymultiplyingboththetopandbottomof23by2.

�� �� =����=����

���� �� =����=��=MCC4.NF.2Comparetwofractionswithdifferentnumeratorsanddifferentdenominators,e.g.,bycreatingcommondenominatorsornumerators,orbycomparingtoabenchmarkfractionsuchas12.Recognizethatcomparisonsarevalidonlywhenthetwofractionsrefertothesamewhole.Recordthe

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resultsofcomparisonswithsymbols>,=,or<,andjustifytheconclusions,e.g.,byusingavisualfractionmodel.Buildfractionsfromunitfractionsbyapplyingandextendingpreviousunderstandingsofoperationsonwholenumbers.Iftwofractionshavedifferentnumeratorsanddenominatorsitisdifficulttodeterminewhichfractionislarger.Itiseasiertodeterminewhichislargerifbothfractionshavethesamedenominator.Step1:Findacommondenominator.Theleastcommondenominatoroftwodenominatorsisactuallythesmallestnumberthatisdivisiblebyeachofthedenominators.

Tofindtheleastcommondenominator,simplylistthemultiplesofeachdenominator(multiplyby2,3,4,etc.outtoabout6orsevenusuallyworks)thenlookforthesmallestnumberthatappearsineachlist.Example:Supposewewantedtocompare512and13.Tofindtheleastcommondenominatorasfollows:• Firstwelistthemultiplesofeachdenominator.Multiplesof12are12,24,36,48,60,…Multiplesof3are3,6,9,12,15,18,21,,…Now,whenyoulookatthelistofmultiples,youcanseethat12isthesmallestnumberthatappearsineachlist.Therefore,theleastcommondenominatorof512and13is12.

Step2:Multiplythenumeratoranddenominatorofonefractionbythesamenumbersobothfractionswillhavethesamedenominator.

• Forexample,if512and13arebeingcompared,13shouldbemultipliedby44.Itdoesnotchangethevalueof13tobemultipliedby44(whichisequalto1)becauseanynumbermultipliedby1isstillthesamenumber.Afterthemultiplication�×� �×� =���thecomparisoncanbemadebetween512and412.So512isgreaterthan412or13.

• Youmayhavetomultiplybothfractionsbydifferentnumberstoproducethesamedenominatorforbothfractions.Forexampleif23and34arecompared,firstwelistthemultiplesofthetwodenominators.

Multiplesof3are3,6,9,12,15,18,…Multiplesof4are4,8,12,16,20,24,…

Next,weneedtomultiply23by44toget812andmultiply34by33toget912.Thefraction34whichisequalto912islargerthan23whichisequalto812.

MCC4.NF.3Understandafraction��witha>1asasumoffractions1/b.

a) Understandadditionandsubtractionoffractionsasjoiningandseparatingpartsreferringtothesamewhole.

b) Decomposeafractionintoasumoffractionswiththesamedenominatorinmorethanoneway,recordingeachdecompositionbyanequation.Justifydecompositions,e.g.,byusingavisualfractionmodel.

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DecompositionofFractionsExamples:38=18+18+18or38=18+28218=1+1+18or88+88+18=218.

c) Addandsubtractmixednumberswithlikedenominators,e.g.,byreplacingeachmixednumberwithanequivalentfraction,and/orbyusingpropertiesofoperationsandtherelationshipbetweenadditionandsubtraction.

Tochange2¾(amixednumber)intoanequivalentfraction:Multiply4x2,thenadd3=11,thisisthenumerator.Usethesamedenominator(4),andtheequivalentfractionis11/4.Ordecomposethemixednumber2¾to44+44+34=114(remember44=1)

d)Solvewordproblemsinvolvingadditionandsubtractionoffractionsreferringtothesamewholeandhavinglikedenominators,e.g.,byusingvisualfractionmodelsandequationstorepresenttheproblem.

MCC4.NF.4Applyandextendpreviousunderstandingsofmultiplicationtomultiplyafractionbyawholenumber.

a.Understandafraction��asamultipleof1�.Forexample,useavisualfractionmodeltorepresent54astheproduct5×14,recordingtheconclusionbytheequation54=5×14.

b.Understandamultipleof��asamultipleof1�,andusethisunderstandingtomultiplyafractionbyawholenumber.

Forexample,useavisualfractionmodeltoexpress3×25as6×15recognizingthisproductas65.Ingeneral,n×��=(�×�) �.

c.Solvewordproblemsinvolvingmultiplicationofafractionbyawholenumber,e.g.,byusingvisualfractionmodelsandequationstorepresenttheproblem.

Decimals

Understanddecimalnotationforfractions,andcomparedecimalfractions.MCC4.NF.5Expressafractionwithdenominator10asanequivalentfractionwithdenominator100,andusethistechniquetoaddtwofractionswithrespectivedenominators10and100.Forexample,express310as30100,andadd310+4100=34100.

110=0.1or0.10 810=0.8or0.80 9100=0.0926100=0.26

MCC4.NF.6Usedecimalnotationforfractionswithdenominators10or100.

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Forexample,rewrite0.62as62100;describealengthas0.62meters;locate0.62onanumberlinediagram.MCC4.NF.7Comparetwodecimalstohundredthsbyreasoningabouttheirsize.Recognizethatcomparisonsarevalidonlywhenthetwodecimalsrefertothesamewhole.Recordtheresultsofcomparisonswiththesymbols>,=,or<,andjustifytheconclusions,e.g.,byusingavisualmodel.Decimalsarecomparedexactlythesamewayaswholenumbers:bycomparingthedifferentplacevaluesfromlefttoright.Tohelpyou,writethetwonumbersintotheplacevaluetablesontopofeachother.Thencomparethedifferentplacevaluesinthetwonumbersfromlefttoright,startingfromthebiggestplacevalue.Withdecimalnumbers,youcannotassumethenumberwiththemostdigitsisthelargestnumber.Seebelow.

Above,thetwonumbershavethesamevalueintheones’place.Next,thedecimalsarecomparedstartingwithtenthsplaceandthenhundredthsplace(ifnecessary).Ifonedecimalhasahighernumberinthetenthsplacethenitislargerthanadecimalwithfewertenths.Ifthetenthsareequalcomparethehundredthsuntilonedecimalislargerortherearenomoreplacestocompare.Ifeachdecimalplacevalueisthesamethenthedecimalsareequal.OperationsandAlgebraicThinking

Usethefouroperationswithwholenumberstosolveproblems.MCC4.OA.1Interpretamultiplicationequationasacomparison,e.g.,interpret35=5×7asastatementthat35is5timesasmanyas7and7timesasmanyas5.Representverbalstatementsofmultiplicativecomparisonsasmultiplicationequations.SeeCommutativePropertyofMultiplication.MCC4.OA.2Multiplyordividetosolvewordproblemsinvolvingmultiplicativecomparison,e.g.,byusingdrawingsandequationswithasymbolfortheunknownnumbertorepresenttheproblem,distinguishingmultiplicativecomparisonfromadditivecomparison.(Seechartonthelastpage)

1.3 1.031.3>1.03

1 .3 1 .0 3

tens’

ones’

tenths

hundredths

2.16 2.52.16<2.5

2 .1 6 2 .5

tens’

ones’

tenths

hundredths

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MCC4.OA.3Solvemultistepwordproblemsposedwithwholenumbersandhavingwhole‐numberanswersusingthefouroperations,includingproblemsinwhichremaindersmustbeinterpreted.Representtheseproblemsusingequationswithaletterstandingfortheunknownquantity.Assessthereasonablenessofanswersusingmentalcomputationandestimationstrategiesincludingrounding.

Solvingforavariable(unknownquantity)inaproblem

AdditionProblems�+23=5422+�=5654–23=3156–22=34�=31�=34

SubtractionProblems�‐23=5456‐�=2254+23=7756–22=34�=77�=34

MultiplicationProblems�x5=657x�=9865÷5=1398÷7=14�=13�=14

DivisionProblems65÷�=598÷�=1465÷5=1398÷14=7�=13�=98

Gainfamiliaritywithfactorsandmultiples.MCC4.OA.4Findallfactorpairsforawholenumberintherange1–100.Recognizethatawholenumberisamultipleofeachofitsfactors.Determinewhetheragivenwholenumberintherange1–100isamultipleofagivenone‐digitnumber.Determinewhetheragivenwholenumberintherange1–100isprimeorcomposite.

Factorpairs:twowholenumbersthatmultipliedtogethertogetaproduct.

Multiples:aproductoftwogivenwholenumbers. multiplesof2:2,4,6,8,10,12,14,16,18,20,… multiplesof8:8,16,24,32,40,48,56,64,72,80,…

Primenumbers:numberswithonefactorpair. 17=1×17 11=1×11Compositenumbers:numberswithmorethanonefactorpairs. 6=1×6 16=1×16 48=1×48 6=2×3 16=2×8 48=2×24 16=4×4 48=4×12 48=6×8Generateandanalyzepatterns.MCC4.OA.5Generateanumberorshapepatternthatfollowsagivenrule.Identifyapparentfeaturesofthepatternthatwerenotexplicitintheruleitself.

Forexample,giventherule“Add3”andthestartingnumber1,generatetermsintheresultingsequenceandobservethatthetermsappeartoalternatebetweenoddandevennumbers.Explaininformallywhythenumberswillcontinuetoalternateinthisway.

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StandardsforMathematicalPracticeStudentsareexpectedto:1.Makesenseofproblemsandpersevereinsolvingthem.

Studentsknowthatdoingmathematicsinvolvessolvingproblemsanddiscussinghowtheysolvedthem.

2.Reasonabstractlyandquantitatively.Whenproblemsolving,studentsshouldconnectthequantitytowrittensymbolsandcreatealogicalrepresentationoftheproblemathand,consideringboththeappropriateunitsinvolvedandthemeaningofquantities.

3.Constructviableargumentsandcritiquethereasoningofothers.Studentsshouldexplaintheirthinkingandmakeconnectionsbetweenmodelsandequations.Studentsshouldexplaintheirthinkingtoothersandrespondtoothers’thinking.

4.Modelwithmathematics.Studentsshouldexperimentwithrepresentingproblemsituationsinmultiplewaysincludingnumbers,words(mathematicallanguage),drawingpictures,usingobjects,makingachart,list,orgraph,creatinganequation,etc.

5.Useappropriatetoolsstrategically.Studentsshouldconsidertheavailabletoolswhensolvingaproblemanddecidewhencertaintoolsmightbehelpful.

6.Attendtoprecision.Studentsshoulduseclearandpreciselanguageinexplainingtheirreasoningwithothers.Theycarefulnotateunitsofmeasureandareabletostatethemeaningofsymbolstheychoose.

7.Lookforandmakeusofstructure.Studentslookcloselytodiscoverapatternorstructure.

8.Lookforandexpressregularityinrepeatedreasoning.Studentsshouldnoticerepetitiveactionsincomputationtomakegeneralizations.Studentsusemodelstoexplaincalculationandunderstandhowalgorithmswork.

Glossaryaddend:numbersthatareaddedtogethercompositenumber:anumberwithmorethanonefactorpair. 12=1×12 2×63×4denominatoristhebottomnumberofthefraction;showshowmanyequalpartstheitemisdividedinto;adivisordifference:answertoasubtractionproblemdigit:numberdividend:thenumberthatanothernumberisdividedinto

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Example:45÷5=9,45isthedividenddivisor:thenumberthatanothernumberisdividedby Example:45÷5=9,5isthedivisorequation:statetwothingsarethesameusingnumbersandmathsymbols.Anequalsignisused. Example:10=1+9 8×2=6+10equivalentfractions:havethesamevalue,butmaylookdifferent(12=24)even:anumberendingwith0,2,4,6,or8.Evennumberscanbeevenlydividedintotwogroups.expandedform:toshowanumberasthesumofthevalueofitsdigitsexpression:partofanumbersentencethathasnumbersandoperationsigns,butithasnoequalsignfactor:numbersthataremultipliedfactorpair:twowholenumbersthatmultipliedtogethertogetoneproductimproperfractions:haveanumeratorwiththehighestnumber,54mixednumber:isawholenumberandafraction,212multiple:aproductoftwogivenwholenumbers. multiplesof8:8,16,24,32,40,48,56,64,72,80,…numbername:toshowanumberasword(s)numeral:theusualwayofwritinganumbernumerator:isthetopnumberofthefraction;howmanyequalpartsyouhaveodd:anynumberthatendswith1,3,5,7,or9.Oddnumberscannotbeevenlydividedintotwogroups.parallellines:linesthatnevercrossperpendicularlines:linesthatmeetorcrossatrightangles(90°)primenumber:anumberwithonefactorpair Examples:3=1×3

17=1×17product:answertoamultiplicationproblem factor×factor=productproperfractions:haveadenominatorwiththehighestnumber,78quotient:answertoadivisionproblem dividend÷divisor=quotientExample:45÷5=9,9isthequotientremainder:theportionthatwillnotmakeacompletegroup Example:21÷5=4R1,1istheremaindersum:answertoanadditionproblem addend+addend=sumvariable:aletterorsymbolthatrepresentsanumberyoudon’tknow.

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