GWD24 03米有问过的~

ConnieC · 发表于 2010-8-7 11:33:46

3 in a certain game played with red chips and blue chips, each red chip has a point value of X and each blue chip has a point value of Y, where X>Y and X and Y are positive integers. If a player has 5 red chips and 3 blue chips, what is the average (arithmetic mean ) point value of the 8 chips that the player has?

(1) The average point value of one red chip and one blue chip is 5.

(2) The average point value of the 8 chips that the player has is an integer.

答案是C，但是我觉得该选E啊~~
思路入下：

求的是（5X+3Y）/(X+Y)

条件1:知道了x+y=10，把上式化简得到并带入前式 3+（2X）/10。得不出。然后由X>Y得 X可以是6,7,8,9 ；Y与之对应的是4,3,2,1。那就有4个答案

条件2：八个数的平均数是整数，也得不出来

条件1+2：我觉得也不能得到答案。把X=6,7,8,9一个个带到3+（2X）/10里面，得不到整数滴~~

望指教！！

GWD24 03米有问过的~

所属分类: GMAT考试

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