The pdf of the exponential distribution is:Originally Posted by sweettea331
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Here , and the required probability is:
which you should be able to evaluate.
RonL
Assume the the time required to download a file from the Internet is exponentially distrubuted with mean equal to 4 minutes. What is the probablity that a download will require at least 2 but not more then 4 minutes. (to five decimal places)?