作者cugir (乌拉拉 噜勒勒)
看板Grad-ProbAsk
标题Re: [理工] [机率]-机率
时间Sun Oct 11 01:11:49 2009
※ 引述《AAJJBurnett (叫我投手)》之铭言:
: Let the random variable X be the number of days that a certain patient needs
: to be in the hospital. Say X has the p.m.f.
: 5-x
: f(x)= ------- x=1,2,3,4.
: 10
: If the patient is to receive from an insurance company 200(元) for each of
: the first two days in the hospital and 100(元) for each day after the first
: two days, what is the expected payment for the hospitalization?
我的想法是.........
f(1)=4/10,住院1天领保险费200元
f(2)=3/10,住院2天........200+200元
f(3)=2/10,....3..........200+200+100元
f(4)=1/10,....4..........200+200+100+100元
所以保险公司要赔的钱期望值为:
4/10*200 + 3/10*400 + 2/10*500 + 1/10*600 = 360
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有错请指教..
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1F:推 AAJJBurnett:没错~~ 3Q 10/11 09:36