GMAT/留學申請專業顧問 Donz 之資訊交流園地

 124.
             Favorable   Unfavorable  Nor sure
 Candidate M    40           20        40
 Candidate N    30           35        35
 以上此表表示100個投票人的意見。What was the number of voters who responded
 "Favorable" for both candidate?

 1)   The number of voters who did not respond “Favorable”for either candidate
      was 40.
 2)   The number of voters who responded “Unfavorable”for both candidates was
       10.

Solution:

        
              將答案分成 "Favorable" and "Not favorable"
              我們畫圖表示 以 Yes/ No 做簡寫
              並且以 M 當成第一個判斷依據

              Candidate M      Candidate N

                                           Yes
                   Yes                   ---> A
                  --->          40     No
                                           ---> B
         100                           Yes
                                           ---> C
                 --->          60      No
                  No                     ---> D

              所以我們要求出 A
              且從 Candidate N 資料得知
              A + C = 35 (A, C 代表對 Candidate N "Favorable")

         (1) 對兩者都不 Favorable 有 40 人
             D = 40, --> C = 60 - 40 = 20
             A = 15

         (2) D 包含了 Unfavorable 和 not sure to both candidates
             Both Unfavorable 只是 D 的一部份
             所以依然求不出 D --> not sufficient

         Answer: A