作者Honor1984 (乔祺对我如此狠)
看板Math
标题Re: [微积] 瑕积分一题
时间Wed May 24 09:37:23 2017
※ 引述《petodog (作梦高手)》之铭言：
: Suppose that a bank teller takes an exponentially distributed length of time
: with mean μ=2 minutes to serve each customer. If there is already one
: customer waiting in line, what is the probability that you will wait for more
: than 6 minutes?
: 不懂要怎麽列式
: 知道用exponential列，但怎麽跟机率扯上关系?
probability density = f(t) = Aexp(-t/2)
∞
1 = ∫f(t)dt = A2 => A = 1/2
0
假如前面一个人刚好这时被服务
则你要等超过6分钟的机率
∞
= ∫f(t)dt = exp(-3)
6
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