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英数第五周周一1.Inaspecialvillagelivesomecats,dogsandotheranimals.20%ofthedogsbelivetheyarecats,and20%ofthecatsbelievetheyaredogs.Andalltherestanimalsarenormal.Oneday,thevillagehead,amonkey,findsthatamongallthecatsanddogs,32%ofthemthinktheyarecats.Weknowthereare180moredogsthancatsinthisvillage,sothereare_______dogs.2.Wehavethreebottlesofsaline,A,BandC,andtheirconcentrationsare20%,18%and16%respectively.Wemixthemtogetherandgetsomesalinewitha18.8%concentration.WeknowBis30gramsheavierthanC,sohowheavyisA?3.Therearetwokindsofsolution,AandB.InA,theconcentrationofalcoholis10%,whiletheconcentrationofsaltis30%.InB,theconcentrationofalcoholis50%,whiletheconcentrationofsaltis10%.Wehave1kiloofA,andwewanttomixAwithBsoastogetsomenewsolutioninwhichtheconcentrationofalcoholisthesameasthatofsalt.SohowmuchBdoweneed?4.GumpwenttovisitTom.Healtogetherwalked1200meters.Forthefirst400meters,hewalkedataspeedof5meterspersecond,andfortherest800meters,hewalkedat2.5meterspersecond.Sowhat’shisaveragespeedofthewholejourney?5.Mr.Wangdriveshome.Heplanstodriveataspeedof40kilometersperhour,butwhenhefinisheshalfofthejourney,hefindsthatthespeedisonly30kilometersperhour.Soinordertogethomeontime,howfastshouldhedriveduringtherestofthejourney?6.AcarplannedtogofromCityAtoCityBin6hours.Afterfinishinghalfofthejourney,thecarbrokedownandstoppedfor30minutes.IfitwantedtoarriveinCityBontime,itsspeedshouldincreaseby12kilometersperhourduringtherestofthejourney.SohowfarisCityAfromCityB?7.Agoatgoestoahilltoeatgrass.Itwalksataspeedof4meterspersecondduringthefirsthalfofthejourney.Then,itrunsataspeedof6meterspersecondduringtherestofthejourney.Sowhat’sitsaveragespeedduringthewholejourney?8.Fiveplayerstookpartinachesscompetition.Therulesareasfollows,eachplayerplaysonematchagainsttheotherplayers.Winningplayerreceivestwopointsandthelosingplayerreceiveszeropoints.Ifamatchendsinadraw,eachplayerreceivesonepoint.Attheendofthematch,fourplayersgot16pointsintotal,sohowmanypointsdidthefifthplayerget?9.Thereweresixteamsinasoccercompetition(Eachteamhastoplayonematchagainsttheotherteams).Therulesareasfollows:thewinningteamreceivesthreepointsandlosingteamreceiveszeropoints.Ifamatchendsinadraw,eachteamreceivesonepoint.Bytheendofthecompetition,therewere6matchesthatendedinadraw,sowhatisthesumofalltheteams’points?10.A,B,C,DandEhaveachessmatchtogether,andeachtwoofthemwillplayagame.Sofar,Ahasplayed4games,Bhasplayed3games,Chasplayed2games,andDhasplayed1game.SohowmanygameshasEplayed?答案：1.240只2.50克3.0.5千克4.3(m/s)5.60(km/h)6.360(km)7.4.8(m/s)8.4(分)9.39(分)10.2