The number of emails a professor receives per day is observed to be a Poisson random variable with variance 81. The professor replies to each email with probability 2/3, independently of all other emails, and each reply takes five minutes to write. What is the expected length of time spent writing email replies per day (to the nearest minute)?

The number of emails a professor receives per day is observed to be a Poisson random variable with variance 81. The professor replies to each email with probability 2/3, independently of all other emails, and each reply takes five minutes to write. What is the expected length of time spent writing email replies per day (to the nearest minute)?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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