The number of daily visitors to an ice cream parlor is Poisson with a mean of 25. Using normal approximation, find the probability that at least 80 people visit the ice cream parlor in a three-day period. (Hint: The number of people who visit in a three-day period will also be Poisson. What are the mean and variance of that distribution?)

The number of daily visitors to an ice cream parlor is Poisson with a mean of 25. Using normal approximation, find the probability that at least 80 people visit the ice cream parlor in a three-day period. (Hint: The number of people who visit in a three-day period will also be Poisson. What are the mean and variance of that distribution?)

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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