# Question

It is known that the incomes of subscribers to a particular magazine have a normal distribution with a standard deviation of $6,600. A random sample of 25 subscribers is taken.

a. What is the probability that the sample standard deviation of their incomes is more than $4,000?

b. What is the probability that the sample standard deviation of their incomes is less than $8,000?

a. What is the probability that the sample standard deviation of their incomes is more than $4,000?

b. What is the probability that the sample standard deviation of their incomes is less than $8,000?

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