# Statistics - Probability Distribution

The time between surface finish problems in a galvanizing process is exponentially distributed with a mean a 40 hours. A single plant operates three galvanizing lines that are assumed to operate independently.

a) What is the probability that none of the lines experience a surface finish problems in 40 hours of operations?

b) What is the probability that all three lines experience a surface finish problem between 20 and 40 hours of operation?

c) Why is the joint probability density function not needed to answer the previous questions?

https://brainmass.com/statistics/probability/statistics-joint-probability-distributions-188599

#### Solution Summary

The expert examines the joint probability distributions for the time between surface finish problems. Neat, step-by-step solutions are provided.

$2.19