Question

URGENT PLEASE HELP 15 POINTS!!!!

A consumer affairs investigator records the repair cost for 22 randomly selected TVs. A sample mean of $83.23 and standard deviation of $22.67 are subsequently computed. Determine the 95% confidence interval for the mean repair cost for the TVs. 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.

Answer 1

Using a t-distribution with 21 degrees of freedom (since n-1 = 22-1 = 21), and a 95% confidence level, we can find the critical value from a t-table or calculator.

The critical value is ±2.080.

Rounded to three decimal places, the critical value is 2.080.