GRE考试易错题(2017/9/27) |
第1题:IfBobcandoajobin20daysandJanecandothejobin30days,theyworktogethertodothisjobandinthisperiod,Bobstopworkfor2.5daysandJanestopworkforxdays,andthejobbefinishedfor14days,whatisx?() A.1.6 B.3.2 C.1.5 D.1.25 E.1.15 |
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第2题:Inaninsurancecompany,eachpolicyhasapaperrecordandanelectricrecord.Forthosepolicieshavingincorrectpaperrecord,60%alsohavingincorrectelectricrecord;Forpolicieshavingincorrectelectricrecord,75%alsohavingincorrectpaperrecord.3%ofallpolicieshavebothincorrectpaperandincorrectelectricrecords.Ifwerandomlypickoutonepolicy,what’stheprobabilitythattheonehavingbothcorrectpaperandcorrectelectricrecords?() A.0.80 B.0.94 C.0.75 D.0.88 E.0.92 |
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第3题:A,B,C,D,E,F排在1,2,3,4,5,6六个位置上,问A不在1,B不在2,C不在3的情况下,共有多少种排法?() A.720 B.450 C.180 D.216 E.320 |
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第4题:Aboxcontains100balls,numberedfrom1to100.Ifthreeballsareselectedatrandomandwithreplacementfromthebox,whatistheprobabilitythatthesumofthethreenumbersontheballsselectedfromtheboxwillbeodd?() A.1/4 B.3/8 C.1/2 D.5/8 E.3/4 |
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第5题:从1,2,3,4,5,6,7,8,9中选出三个数字组成一个三位数,这个三位数的digits中有两个相同,另一个digit与其它两个都不同,问共有多少个这样的三位数?() A.72 B.144 C.180 D.216 E.54 |
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