Board logo

标题: GWD3-30 [打印本页]

作者: luoye1    时间: 2005-7-15 06:57     标题: GWD3-30

Q30:

M = {-6, -5, -4, -3, -2}

T = {-2, -1, 0, 1, 2, 3}

If an integer is to be randomly selected from set M above and an integer is to be randomly selected from set T above, what is the probability that the product of the two integers will be negative?

A. 0

B. 1/3

C. 2/5

D. 1/2

E. 3/5

我只会用穷局法,好累,而且算不出结果,有更好的办法么?我算出来是11/20?


作者: himba    时间: 2005-7-15 07:28

从M中任选一个是负数, 而要满足2个数的乘积是正,则只要考虑从T中选出负数

的概率. 很容易得出是1/2.






欢迎光临 国际顶尖MBA申请交流平台--TOPWAY MBA (http://forum.topway.org/) Powered by Discuz! 7.2