匿名使用者
匿名使用者 發問時間: 科學數學 · 1 0 年前

一題關於概率的題目...help(大學.)

The lifetimes of six major components in a copier are independent exponential random variables with means of 8000, 10,000, 10,000, 20,000, 20,000, and 25,000 hours, respectively.

a.

What is the probability that the lifetimes of all the components exceed 5000 hours?

b.

What is the probability that at least one component lifetime exceeds 25,000 hours?

這題我不會耶,.....是課本上的題目 看起來好像蠻簡單的可是我不會= =

不要只給答案 要給過程唷拜託 ><

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