A researcher records the repair cost for 8 randomly selected washers. A sample mean of $60.46 and standard deviation of $18.36 are subsequently computed. Determine the 90% confidence interval for the mean repair cost for the washers. Assume the population is approximately normal.
Step 1 of 2: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
A researcher records the repair cost for 8 randomly selected washers. A sample mean of $60.46 and standard deviation of $18.36 are subsequently computed. Determine the 90% confidence interval for the mean repair cost for the washers. Assume the population is approximately normal.
Step 2 of 2: Construct the 90% confidence interval. Round your answer to two decimal places.
Find the Lower endpoint and upper endpoint