# Probability Mass Function, Mean and Variance

A lot consisting of 100 fuses is inspected by the following procedure: 5 fuses are selected randomly, and if all 5 "blow" at the specified amperage, the lot is accepted. Suppose that the lot contains 10 defective fuses. Find the probabily of accepting the lot.

HINT: Let X ba a r.v. equil to the number of defective fuses in the sample of 5 and the result of the r.v. X is known as the "hypergeometric" r.v. with parameters (N,r,n)

(a) Find the pmf of X.

(b) Find the mean and variance of X.

https://brainmass.com/math/probability/probability-mass-function-mean-variance-58579

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A lot consisting of 100 fuses is inspected by the following procedure: 5 fuses are selected randomly, and if all 5 "blow" at the specified amperage, the lot is accepted. Suppose that the lot contains 10 defective fuses. Find the probabily of accepting the lot.

HINT: Let ...

#### Solution Summary

Probability Mass Function, Mean and Variance are investigated. The number of defective fuses in the sample are provided.