问一道简单的数学题

lxw19 · 发表于 2010-9-26 15:41:34

A shipment of 8 television sets contains 2 black-and-white sets and 6color sets. If 2 television sets are to be chosen at random from this shipment, what is the probability that at least 1 of the 2 sets chosen will be a black-and-white set?

1/7B. ¼C. 5/14D. 11/28E. 13/26

这道题答案给的是E，可是我很不理解分母上明明应该是28啊C（8,2），为什么答案的分母是26呢~~我是不是忽略了什么细节~~求教

andreasyang · 发表于 2010-9-26 16:04:04

E应该是13/28，答案打错了

lxw19 · 发表于 2010-9-26 16:09:06

E应该是13/28，答案打错了

-- by 会员 andreasyang (2010/9/26 16:04:04)

谢谢你这套题做得我好郁闷啊~~哎

问一道简单的数学题

所属分类: GMAT考试

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