The owner of a small convenience store is trying to decide whether to discontinue selling magazines. He suspects that only 5% of the customers buy magazines and thinks that he might be able to sell something more profitable. Before making a final decision, he keeps track of the number of customers who buy magazines on a given day. a. On one day, he had 280 customers. Assuming this day was typical, what would be the mean and standard deviation of the number of customers who buy magazines each day? b. What is the probability that less than 10 people will buy a magazine that day? c. What is the probability that more than 20 people will buy a magazine that day?

The owner of a small convenience store is trying to decide whether to discontinue selling magazines. He suspects that only 5% of the customers buy magazines and thinks that he might be able to sell something more profitable. Before making a final decision, he keeps track of the number of customers who buy magazines on a given day. a. On one day, he had 280 customers. Assuming this day was typical, what would be the mean and standard deviation of the number of customers who buy magazines each day? b. What is the probability that less than 10 people will buy a magazine that day? c. What is the probability that more than 20 people will buy a magazine that day?

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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