Approximately 1% of the US population currently have active coronavirus. According to Johns Hopkins, a particular type of COVID test (RT-PCR), has a false negative rate of 20%. That is, if a person has COVID, and takes this test, there is a 20% chance of testing negative. The false positive rate is about 1% (more recent COVID tests have a false positive rates around .4%). That means that about 1% of people who don’t have COVID will nonetheless test positive. Consider the following two-way table for 1000 randomly selected people who were tested for COVID using (RT-PCR). Positive test Negative test Total Has COVID 8 2 10 No COVID 10 980 990 Total 18 982 1000 What is the probability of choosing someone who tested positive? What is the probability of choosing someone who has COVID? What is the probability of choosing someone who Doesn’t have COVID andtested positive? What is the probability of choosing someone with COVID given that they testedpositive?

Approximately 1% of the US population currently have active coronavirus. According to Johns Hopkins, a particular type of COVID test (RT-PCR), has a false negative rate of 20%. That is, if a person has COVID, and takes this test, there is a 20% chance of testing negative. The false positive rate is about 1% (more recent COVID tests have a false positive rates around .4%). That means that about 1% of people who don’t have COVID will nonetheless test positive. Consider the following two-way table for 1000 randomly selected people who were tested for COVID using (RT-PCR). Positive test Negative test Total Has COVID 8 2 10 No COVID 10 980 990 Total 18 982 1000 What is the probability of choosing someone who tested positive? What is the probability of choosing someone who has COVID? What is the probability of choosing someone who Doesn’t have COVID andtested positive? What is the probability of choosing someone with COVID given that they testedpositive?

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Holt Mcdougal Larson Pre-algebra: Student Edition 2012

1st Edition

ISBN:9780547587776

Author:HOLT MCDOUGAL

Publisher:HOLT MCDOUGAL

Chapter11: Data Analysis And Probability

Section: Chapter Questions

Problem 8CR

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