Question

3. The same radio station wants to track the average number of commercial minutes it plays in an hour. A random sample over the past month yielded the following data in minutes: 15.5, 10.2, 8.2, 16, 14.4, 9.5, 8.9, 11.4, 16.3, and 15.2.A. Compute a 99% confidence interval for the mean number of commercial minutes played in an hour.

Answer 1

Answer: 10.09 or 15.03

Step-by-step explanation:

Formula for confidence interval(CI) is CI = x ± z * (sd/ Sqrt(n))

Where x is mean = 12.56

z is value for normal distribution 99% confidence =2.58

sd is standard deviation=3.03

Sqrt is square root

n is sample population = 10

CI =12.56±2.58*(3.03/sqrt(10)

=12.56±2.47

=15.03 or 10.09

With 99% confidence, the average number of commercial minutes is between 10.09 and 15.03 minutes, based on sample data.