According to a recent report, people smile an average of μ = 62 time per day. Assuming that the distribution of smiles is approximately normal with a standard deviation of σ = 18, find each of the following values. a.What proportion of people smile more than 80 times a day b.What proportion of people smile at least 50 times a day?

According to a recent report, people smile an average of μ = 62 time per day. Assuming that the distribution of smiles is approximately normal with a standard deviation of σ = 18, find each of the following values. a.What proportion of people smile more than 80 times a day b.What proportion of people smile at least 50 times a 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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