※ 引述《candyme ()》之銘言： : 15. : Tanks A and B are each in the shape of a right circular cylinder. : The interior of tank A has a height of 10 meters and a circumference : of 8 meters and a circumference of 10 meters. The capacity of tank A : is what percent of the capacity of tank B ? : A.75% : B.80% : C.100% : D.120% : E.125% : ANS: B This question is incomplete. : 16. : Meg and Bob are among the 5 participants in a cycling race. If each : participant finishes the race and no two participants finish at the : same time, in how many different possible orders can the participants : finish the race so that Meg finishes ahead of Bob ? : A.24 : B.30 : C.60 : D.90 : E.120 : ANS:C : Thanks for your help!!! 4!+C3取1*3!+C2取1*3!+3! =24+18+12+6 =60 ^^^^^^^^Meg as Rank2, Bob can be one of three participants behind, and multiple premutation of other 3 players. Logic: First decide the rank of Meg and Bob, then consider the premutation of other 3 participants. ***Hope this helps to answer. --

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