A record store owner knows that 25% of customers entering her store make a purchase.Consider a random sample consisting of 100 customers who entered the store.(a) What is the mean and variance of the sample proportion of customers making apurchase?(b) What is the probability that the sample proportion is less than 0.20?(c) She calculated the probability that the sample proportion is lower than a propor-tion a, and the probability turned out 0.05. Then what is this number a?

Let p be the proportion of customers entering the store make a purchase. Given that p = 0.25 Also,…

Answered: What is the mean and variance of the…

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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