国际顶尖MBA申请交流平台--TOPWAY MBA

标题: TT-3-28 [打印本页]

作者: lxj19820127 时间: 2006-11-12 06:55 标题: TT-3-28

If x and y are integers and x > 0, is y > 0?

(1) 7x – 2y > 0

(2) -y < x

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient.

答案E

作者: luolihua73 时间: 2006-11-12 18:54

x>0

(1) x>(2/7)y

(2)x>-y

根据已知条件不能推出y 是大于0的整数

hmm,it should be E

作者: lewis 时间: 2006-11-13 06:50

(1)--> y<(7/2）x
(2)--> y>-x
so -x < y < (7/2)x, 所以y不定

作者: lewis 时间: 2006-11-14 06:50

代入法,设定特殊值,不要试图找规律证明

作者: 叮叮当当 时间: 2006-11-15 06:54

试一下X=2, Y=1; X=2, Y=-1

欢迎光临国际顶尖MBA申请交流平台--TOPWAY MBA (http://forum.topway.org/)