I am having alot of trouble with a homework question from my book. It asks:(adsbygoogle = window.adsbygoogle || []).push({});

The time between unplanned shutdowns of a power plant has an exponential distribution with a mean of 20 days. Find the probability that the time between two unplanned shutdowns is more than 21 days.

I know this much so far 1-e-(20)(?) (one minus e to the negative power of mean times any value of the continuous variable(X))

I am lost on finding X within the equation.

Hope someone can help.

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# Homework Help: Exponential Distribution

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