INTRODUCTION TO STATISTICS & DATA ANALYS

6th Edition

ISBN: 9780357420447

Author: PECK

Publisher: CENGAGE L

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Textbook Question

Chapter 6.5, Problem 68E

Refer to the previous exercise. Suppose now that for a probability question, 100 answers are submitted, of which 50 are correct. Calculate the probabilities in Parts (a) and (b) of the previous exercise for the probability question.

6.67 The National Public Radio show Car Talk used to have a feature called “The Puzzler.” Listeners were asked to send in answers to some puzzling questions—usually about cars but sometimes about probability (which, of course, must account for the incredible popularity of the program!).

Suppose that for a car question, 800 answers were submitted, of which 50 are correct.

a. Suppose that the hosts randomly select two answers from those submitted with replacement. Calculate the probability that both selected answers are correct. (For purposes of this problem, keep at least five digits to the right of the decimal.)
b. Suppose now that the hosts select the answers at random but without replacement. Use conditional probability to evaluate the probability that both answers selected are correct. How does this probability compare to the one computed in Part (a)?

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Chapter 6.5, Problem 67E

Chapter 6.6, Problem 69E

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Chapter 6 Solutions

INTRODUCTION TO STATISTICS & DATA ANALYS

Ch. 6.1 - Define the term chance experiment, and give an...Ch. 6.1 - Define the term sample space, and then give the...Ch. 6.1 - Consider the chance experiment in which the type...Ch. 6.1 - Refer to the chance experiment described in the...Ch. 6.1 - A tennis shop sells five different brands of...Ch. 6.1 - Refer to the chance experiment described in the...Ch. 6.1 - A new model of laptop computer can be ordered with...Ch. 6.1 - A college library has four copies of a certain...Ch. 6.1 - A library has five copies of a certain textbook on...Ch. 6.1 - Suppose that, starting at a certain time,...

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Solution Summary: The author calculates the probability that both selected answers are correct using conditional probability and compares it with part (a).

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