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1、思维题分享1.Calculate:1+12+14+18+161+321+641+1281+2561=_______.1=147a+1340b+1c+12.Ifd,anda,b,c,dareallnonzeronaturalnumbers,soa+b+c+d=_______.3.Select3consecutivenaturalnumbersfrom1to2018,sothattheirproductcanbedividedby30.Howmanychoicearethere?4.Divide60chesspiecesinto27piles,with1,2or5piecesineac
2、hpile,Ifthesumofthenumberofthepileswith2piecesand5piecesare2timesofthenumberofthepileswith1piece,sohowmanypileswith2piecesarethere?5.Filltwoadjacentintegersintheblanks.___<109+1011+.....+1718+1918<____6.Thereare2019dwarfs,andtheyareeithergoodpeopleorbadpeople.Theywilltakepartinapartyeveryday.A
3、ndthenumberofthedwarfstakingpartinthepartyisthemultipleof3or5.Amongthepeopletakingpartintheparty,ifthegoodpeopleareinthemajority,allthepeopleinthepartywillbecomegoodpeople.Ifthebadpeopleareinthemajority,allthepeopleinthepartywillbecomebadpeople.Thequestionis:Allthepeoplebecomegoodpeopleifthepa
4、rtyonthethirddayends,what’sthenumberofthegoodpeoplebeforethepartyofthefirstdayatleast?7.Tomtakespartinatestsixtimes.Theaveragescoreofthethirdandfourthtimeis2scorehigherthantheaveragescoreofthefirsttwotimesandis2scorelowerthantheaveragescoreofthelasttwotimes.Iftheaveragescoreofthelastthreetimes
5、is3scorehigherthantheaveragescoreofthefirstthreetimes,thenwhat’sthescoreofthefourthtest?8.PlaceAis2.8kilometersawayfromPlaceB.Twodogskeeprunningbetweenthesetwoplaces.Theyrunatspeedsof450and350metersperminuterespectively.Theyfirstruntowardseachotherfor1minute,andthentheyturnbackandruninopposite
6、directionsforanother2minutes.Then,theyturnbackagainandruntowardseachotherfor3minutes,andthenturnbackandrunfor4minutes…Theykeeprunninginthiswayuntiltheymeet.Sohowsoonwilltheymeet?解析：1.1+12+14+18+161+321+641+1281+2561=_______.【解析】原式=1+12+14+18+161+321+641+1281+2561+2561-2561=2-2561=1256255.2.若1=
7、147，且a,b,c,d均为非0自然数，则a+b+c+d=______.a+13401b+c+1d【解析】1=147=1=1×××a+13403402+46b+1147147c+1d340÷147=2....46,即a=2147÷46=3....9,即b=346÷9=5....1,即c=59÷1=9，即d=9所以a+b+c+d=2+3+5+9=193.从1～2018中选出连续3个自然数，使得它们的乘积能被30整除，一共有______种选法．【解析】因为是连续选的3个数
