请教一道概率题

菜鸟东南飞

The probability that event M will not occur is 0.8 and the probability that event R will not occur is 0.6. If events M and R cannot both occur, which of the following is the probability that either event M or event R will occur?
A) 1/5 B) 2/5 C) 3/5 D) 4/5 E) 12/25

你看看这题，和上面那题有啥不一样，答案C

菜鸟东南飞

请问你这是哪里来的题目，我觉得这题答案有问题啊

菜鸟东南飞

VincentFSJ 发表于 2016-9-17 11:39
nope：
p=1-p（t不得奖）*p（j不得奖）
按lz的思路正向思考

你这个公式，只能用在独立事件上吧，然而此题应该是互斥事件