Contaminated gun cartridges. Refer to the investigation of contaminated gun cartridges at a weapons manufacturer, presented in Exercise 4.29 (p. 226). In a sample of 158 cartridges from a certain lot, 36 were found to be contaminated, and 122 were “clean.” If you randomly select 5 of these 158 cartridges, what is the probability that all 5 will be “clean”?

Short Answer

Expert verified

The probability that all 5 will be clean is 0.20.

Step by step solution

01

Given Information

A lot contains 158 cartridges.

N=158M=36N-M=122n=5

02

Hypergeometric Distribution is used to find the probability

The probability is calculated as

px=0=M0×N-MN-0Nn=360×1225-01580=1×207288004769754986=0.26

Therefore, the probability is 0.26.

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