两袋黑白球:怎样分配让你赢面最大?
100 balls: 50 white and 50 black and two sacks.
题目详情
有 100 个球:50 个白球、50 个黑球,以及两只袋子。你可以任意把球分配到两只袋子里。
之后我会选择其中一只袋子(等概率)并从该袋随机摸出一个球:若摸到黑球我赢,摸到白球你赢。
你如何分配,才能使你赢(摸到白球)的概率最大?
Let's play a game with 100 balls: 50 white and 50 black and two sacks. You can arrange the balls within the two sacks in any way you want. I then come into the room and pick a ball from one of the sacks. If I pick a black, I win; a white, you win. How do you arrange the balls such that you have the highest chance of winning?
解析
最优分配是:
- 袋 1:放 1 个白球;
- 袋 2:放剩余的 49 白 + 50 黑(共 99 个)。
则赢的概率为
这是经典最优解。