In a certain city, 40% of households have a total annual income of at least $70,000. A simple random sample of 15 households is selected. Find the probability that: A. 8 households have an annual income of $70,000 or more B. The first household to have an income over $70,000 is the 9th household selected. C. What is the expected number of households with an income over $70,000 D. What is the standard deviation

In a certain city, 40% of households have a total annual income of at least $70,000. A simple random sample of 15 households is selected. Find the probability that: A. 8 households have an annual income of $70,000 or more B. The first household to have an income over $70,000 is the 9th household selected. C. What is the expected number of households with an income over $70,000 D. What is the standard deviation

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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