Every morning a math instructor picks out two socks completely at random from his closet; there's only a 20% chance they match. If they don't match there is a 60% chance his students will laugh at him, while if his socks do match there is only a 10% chance of his students laughing at him. On a given day, what is the probability that his students laugh at him?

Every morning a math instructor picks out two socks completely at random from his closet; there's only a 20% chance they match. If they don't match there is a 60% chance his students will laugh at him, while if his socks do match there is only a 10% chance of his students laughing at him. On a given day, what is the probability that his students laugh at him?

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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