At the beginning of October of 2020, based upon the results of over 1.5 million antibody tests, it was determined that 27% of New York City residents had COVID-19 antibodies. Suppose we took a random sample of n=19 New York City residents at the beginning of October. Let X = the number of these selected residents who have COVID-19 antibodies. (Do not use a normal approximation for this problem. This is a binomial problem.) a) What is the probability that X < 6? b) What is the probability that 5 ≤ X ≤ 7? c) What is the probability that X = 6?

At the beginning of October of 2020, based upon the results of over 1.5 million antibody tests, it was determined that 27% of New York City residents had COVID-19 antibodies. Suppose we took a random sample of n=19 New York City residents at the beginning of October. Let X = the number of these selected residents who have COVID-19 antibodies. (Do not use a normal approximation for this problem. This is a binomial problem.) a) What is the probability that X < 6? b) What is the probability that 5 ≤ X ≤ 7? c) What is the probability that X = 6?

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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