※ 引述《jazzbruce (小布)》之铭言： : ※ 引述《candyme ()》之铭言： : : 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. 怎麽会不完整 = =a 题目: 圆周比 8:10 高 10:8 问容量比 圆周公式 2拍r (拍不知道怎麽打) =>则半径比 8:10 = 4:5 面积公式 拍r平方 => 16:25 所以 体积比 = 16*10 : 25*8 = 4:5 所以就可以得出答案了 我碰到这种问题都是化成100 => 80 :100 所以A的容量就是B容量的80% 以上 希望有帮助 有错请指正 : : 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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