The Average Natural Gas Bill for a Random Sample of 26

question 32

Multiple Choice

The average natural gas bill for a random sample of 26 homes in the 19808 zip code during the month of March was $305.30 with a sample standard deviation of $46.50. The 80% confidence interval around this sample mean is ______ .

• A)($293.30, $317.30)
• B)($268.82, $341.78)
• C)($277.94, $332.66)
• D)($287.06, $323.54)

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Definitions:

Prime Rate

The interest rate that commercial banks charge their most creditworthy customers, usually large corporations.

Repayment Schedule

A detailed plan of the amounts and timing of payments to be made on a loan.

Loan

An amount of money lent out that is to be returned with a specified interest.

T-Bill

Treasury Bill, a short-term government security issued at a discount from the face value and pays no interest before it matures.