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IMAGINE, THINK, and DO
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--- S. Muthu Muthukrishnan

Local Notes

Local Notes 是一款 Windows 下的笔记系统.

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注: 自 v0.550 开始, Calculator 更名为 Sowya. [Sowya] 是吴语中数学的发音, 可在 cn.bing.com/translator 中输入 Sowya, 听其英语发音或法语发音.

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概率统计 >> 概率论

Questions in category: 概率论 (Probability).

[Exer12-2] Exercise 55 of Book {Devore2017B} P.177

Posted by haifeng on 2020-05-08 09:03:56 last update 2020-05-10 22:13:31 | Answers (1)

Suppose the time (in hours) taken by a homeowner to mow his lawn(修剪他的草坪) in an rv $X$ having a gamma distribution with parameters $\alpha=2$ and $\beta=\frac{1}{2}$. What is the probability that it takes:

(a) At most $1$ hour to mow the lawn?
(b) At least $2$ hours to mow the lawn?
(c) Between $.5$ and $1.5$ hours to mow the lawn?