The mean annual income for people in a certain city (in thousands of dollars) is 42,...

The mean annual income for people in a certain city (in thousands of dollars) is 42, with a standard deviation of 30. A pollster draws a sample of 92 people to interview.

A) What is the probability that the sample mean income is less than 37? Round the answer to at least four decimal places.

B) What is the probability that the sample mean income is between 40 and 44? Round the answer to at least four decimal places.

C) Find the 70^th percentile of the sample mean. Round the answer to at least one decimal place.

D) Would it be unusual for the sample mean to be less than 37? Round the answer to at least four decimal places.

E) Do you think it would be unusual for an individual to have an income of less than 37? Explain. Assume the variable is normally distributed. Round the answer to at least four decimal places.

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orchestra answered 1 year ago

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