Lemma
EasyContinuous distributions
OpenStax, Introductory Statistics 2e §5.3 The Exponential Distribution · Try It 3 · Probability · Continuous distributions

The Exponential Distribution · Try It 3

On average, a pair of running shoes can last 18 months if used every day. The length of time running shoes last is exponentially distributed. What is the probability that a pair of running shoes last more than 15 months? On average, how long would six pairs of running shoes last if they are used one after the other? Eighty percent of running shoes last at most how long if used every day?

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OpenStax, Introductory Statistics 2e · §5.3 The Exponential Distribution · Try It 3

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