[求助]prep.MATH

zcdmx09 · 发表于 2008-6-18 08:53:00

65.
Of the 60 animals on a certain farm, 2/3 are either pigs or cows. How many of the animals are cows?

(1)
the farm has more than twice as many cows at it has pigs. 是pigs > 2*cows还是cows>2*pigs呢

(2)
The farm has more than 12 pigs

这道题选C,为什么呢?我怎么感觉选E呢

Q2. 2+2+2^2+2^3+2^4+…..+2^8=?

[此贴子已经被作者于2008-6-18 9:51:18编辑过]

proudking · 发表于 2008-6-18 09:13:00

cows>2*pigs

还有个隐含条件，所有的数字都是正整数，这样就有答案了

zcdmx09 · 发表于 2008-6-18 09:49:00

谢谢,明白了,P+C=40,c>2p,且p>12 -------这样只能取到p=13,c=27 所以选Ｃ

所属分类: GMAT考试