On the basis of data obtained from the National Institute of Dental Research, it has been determined that 42% of 12 -year-olds have never had a cavity, 34% of 13 -year-olds have never had a cavity, and 28% of 14 -year-olds have never had a cavity. Suppose a child is selected at random from a group of 24 junior high school students that includes six 12 -year-olds, eight 13 -year-olds, and ten 14 -year-olds. If this child does not have a cavity, what is the probability that this child is 14 years old?

On the basis of data obtained from the National Institute of Dental Research, it has been determined that 42% of 12 -year-olds have never had a cavity, 34% of 13 -year-olds have never had a cavity, and 28% of 14 -year-olds have never had a cavity. Suppose a child is selected at random from a group of 24 junior high school students that includes six 12 -year-olds, eight 13 -year-olds, and ten 14 -year-olds. If this child does not have a cavity, what is the probability that this child is 14 years old?

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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