Re: [問題] 請問這兩題數學的題意？

看板GRE作者WDS (過去的事就算了~~嘆)時間16年前 (2008/03/25 20:42)推噓2(2推 0噓 2→)

留言4則, 2人參與討論串4/4 (看更多)

※ 引述《shugh (我)》之銘言： : 1. the odds in favor of winning a game can be found by compting the ratio : of the probability of winning to the probability of not winning. : if the probability that Pat will a game is 4/9, what are the odds that : Pat will the game? : (A) 4 to 5 : (B) 4 to 9 : (C) 5 to 4 : (D) 5 to 9 : (E) 9 to 5 : ANS:A odds=P(winning)/P(not winning) 然後題目現在告訴你 Pat wins the game=4/9 所以Pat doesn`t win the game=5/9 then odds=(4/9)/(5/9) =4/5 比值是4/5 則比例就是4 to 5 : 2. if one number is chosen at random from the first 1000 positive integers, : what is the probability that the number chosen is an integer of both : perfect square and cube? : (A)1/1000 : (B)1/500 : (C)3/1000 : (D)1/250 : (E)1/200 : ANS:C : 拜託了！今天看了好久還是看不太懂...>"< 題目問你前壹千個正整數裡是平方數也是立方數的機率是多少 1=1^2=1^3 (1的平方和1的立方都等於1) 64=4^3=8^2 (4的立方和8的平方都等於64) (3^2)^3=(3^3)^2=3^6 (9的立方和27的平方都等於729) 所以總共有3個數 1.64.729 則機率=3/1000 以上這些都是徐老師的補充講義吧 @@ 加油喔~~~ -- -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 220.141.35.50

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