作者msu (do my best)
看板Grad-ProbAsk
标题[理工] [机率]-请问一题
时间Thu Aug 6 12:21:02 2009
Suppose a fair coin is tossed n times.
Each coin toss costs d dollars and the reward is obtaining X heads is
2
aX +bx Find the expected value of the net reward.
请问这题如何解^^
感谢~~
他答案给
1 1 1
a(---n+---n^2)+b(---n)-nd
4 4 2
不过我不是很懂他怎如何求的...
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※ 编辑: msu 来自: 118.167.232.78 (08/06 15:32)
※ 编辑: msu 来自: 118.167.232.78 (08/06 16:07)