A city commissioner claims that 80% of the people living in the city favour contracting out garbage collection to a private company. To test the commissioner's claim, 25 city residents are randomly selected, yielding 22 who prefer contracting to a private company. (a) If the commissioner's claim is correct, what is the probability that the sample would contain at least 22 who prefer contracting to a private company? (b) If the commissioner's claim is correct, what is the probability that exactly 22 would prefer contracting to a private company? (c) If 100 city residents are randomly selected, how many would you expect to prefer contracting to a private company.

A city commissioner claims that 80% of the people living in the city favour contracting out garbage collection to a private company. To test the commissioner's claim, 25 city residents are randomly selected, yielding 22 who prefer contracting to a private company. (a) If the commissioner's claim is correct, what is the probability that the sample would contain at least 22 who prefer contracting to a private company? (b) If the commissioner's claim is correct, what is the probability that exactly 22 would prefer contracting to a private company? (c) If 100 city residents are randomly selected, how many would you expect to prefer contracting to a private company.

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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