# Question

In a large city it was found that summer electricity bills for single-family homes followed a normal distribution with a standard deviation of $100. A random sample of 25 bills was taken.

a. Find the probability that the sample standard deviation is less than $75.

b. Find the probability that the sample standard deviation is more than $150.

a. Find the probability that the sample standard deviation is less than $75.

b. Find the probability that the sample standard deviation is more than $150.

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