1. Suppose a subdivision on the southwest side of Denver, Colorado, contains 1,700 houses. The subdivision was built in 1983. A sample of 110 houses is selected randomly and evaluated by an appraiser. If the mean appraised value of a house in this subdivision for all houses is $229,000, with a standard deviation of $8,500, what is the probability that the sample average is greater than $230,500?

(Round the values of z to 2 decimal places. Round your answer to 4 decimal places.)

2.Suppose the average checkout tab at a large supermarket is $65.12, with a standard deviation of $21.45. Twenty-three percent of the time when a random sample of 45 customer tabs is examined, the sample average should exceed what value? (Round your answer to 3 decimal places.)

3. Suppose a population proportion is .40, and 80% of the time when you draw a random sample from this population you get a sample proportion of .35 or more. How large a sample were you taking?

(Round your answer to the nearest integer.)

n=