GRE数学经典题目及答案分享（1）_GRE数学

GRE数学经典题目及答案分享（1）

　　3.A certain store sells two types of pens: one type for $2 per pen and the

　　other type for $3 per pen. If a customer can spend up to $25 to buy pens at

　　the store and there is no sales tax, what is the greatest number of pens the

　　customer can buy?

　　A 9

　　B 10

　　C 11

　　D 12

　　E 20

　　这个题首先就可以想到单价越便宜的我就能买的越多，因为它没有说两种笔一定要都买。

　　4.A list of numbers has a mean of 8 and a standard deviation of 2.5. If x is a

　　number in the list that is 2 standard deviations above the mean, what is the

　　value of x ?

　　x=_8+2.52=13_这道题不知怎么的，读题的时候度饶了，感觉很费解，什么是两个标准差，以为是个什么特殊的东西，后来问了同学才知道这就是个简单的计算题，没啥特别的，我的个汗啊，考试的时候我碰到了，我肯定错了。。

　　5.Frequency Distribution for List X

　　Number 1 2 3 5

　　Frequency 10 20 18 12

　　Frequency Distribution for List Y

　　Number 6 7 8 9

　　Frequency 24 17 10 9

　　List X and list Y each contain 60 numbers. Frequency distributions for each list are given above. The average of the numbers in list X is 2.7, and the average of the numbers in list Y is 7.1. List Z contains 120 numbers: the 60 numbers in list X and the 60 numbers in list Y.