GWD20-20

meckychen · 发表于 2010-1-6 16:51:24

Q20:

What is the ratio of the average (arithmetic mean) height of students in class X to the average height of students in class Y?

(1) The average height of the students in class X is 120 centimeters.

(2) The average height of the students in class X and class Y combined is 126 centimeters.

Answer is E

what's the meaning of combined?

meckychen · 发表于 2010-1-6 19:29:52

a10285 · 发表于 2010-1-6 19:46:24

X and class Y combined
指的是X和Y的并集x∪y

而 x和y的数量关系并不清楚，
因而（1）+（2）也得不出答案~

meckychen · 发表于 2010-1-7 11:54:18

thank you

GWD20-20

所属分类: GMAT考试

正在浏览此版块的会员 ()

浏览过的版块