The probability of a randomly selected adult in one country being infected with a certain virus is 0.006. In tests for the virus, blood samples from 21 people are combined. What is the probability that the combined sample tests positive for the virus? Is it unlikely for such a combined sample to test positive? Note that the combined sample tests positive if at least one person has the virus. The probability that the combned sample will test postive is __ (round to three decimal places as needed)

The probability of a randomly selected adult in one country being infected with a certain virus is 0.006. In tests for the virus, blood samples from 21 people are combined. What is the probability that the combined sample tests positive for the virus? Is it unlikely for such a combined sample to test positive? Note that the combined sample tests positive if at least one person has the virus. The probability that the combned sample will test postive is __ (round to three decimal places as needed)

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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