建议使用官方纸质指南,查看对照完整题目
【OG20-P293-451题】
Are all of the numbers in a certain list of 15 numbers equal?
(1) The sum of all the numbers in the list is 60.
(2) The sum of any 3 numbers in the list is 12.
分析A选项
分析B选项
分析C选项
分析D选项
分析E选项
(1)15个数之和等于60不能保证15个数相等,可能性很多;
(2)任意3个数字之和等于12,经试验只有当所有的数字都等于4时才能满足条件;
所以选B。
purity
OK. Let's name the 15 numbers by letters, a, b, c, d, ... Consider a, b, and c, three arbitrary numbers from the list; we know from (2) that a + b + c= 12 (I) Now consider a, b and d; we know from (2) that a + b + d= 12 (II) From (I) and (II) we have: a + b + c = a+ b + d ---> c=d We can again consider a + b + d, a + b + e , ... and prove that d=e and hence c = d = e In the similar way it can be proved that a = b = c = d = e = f = ...
勇敢的狗勾
经试验只有当所有的数字都等于4时才能满足条件?? 有谁有更好的方法吗。。。。
1m27s
平均耗时
79.5%
平均正确率
该题由网友9OQ3P31提供 上传GMAT题