A drug-screening test is used in a large population of people of whom 4% actually use drugs. Suppose that the false positive rate is 3% and the false-negative rate is 2%. Thus a person who uses drugs tests positive for 98% of the time, and a person who does not use drugs tests negative for 97% of the time. (Use Bayes’ Theorem) (a) What is the probability that a randomly chosen person who tests positive for drugs actually uses drugs? (b) What is the probability that a randomly chosen person who tests negative for drugs does not use drugs?

A drug-screening test is used in a large population of people of whom 4% actually use drugs. Suppose that the false positive rate is 3% and the false-negative rate is 2%. Thus a person who uses drugs tests positive for 98% of the time, and a person who does not use drugs tests negative for 97% of the time. (Use Bayes’ Theorem) (a) What is the probability that a randomly chosen person who tests positive for drugs actually uses drugs? (b) What is the probability that a randomly chosen person who tests negative for drugs does not use drugs?

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Description: A drug-screening test is used in a large population of people of whom 4% actually use drugs. Suppose that the false positive rate is 3% and the false-negative rate is 2%. Thus a person who uses drugs tests positive for 98% of the time, and a person w

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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