Question

7.   Confidence Intervals

The fast food industry continues to be very competitive and Wendy’s is seeking to understand their clientele.    Wendy’s sough to estimate the average satisfaction score for 915 customers.  The firm’s goal is to achieve an average satisfaction score of at least 80 on a scale of 0-100.  A random sample of 80 customers had an average satisfaction score of 82.7 and a sample standard deviation of 6.7

a.   Construct a 95% confidence interval to estimate the actual average  from 2019 satisfaction score.

b.   Based on this sample, can they conclude that Wendy’s has reached its goal?

8.   Hypothesis Testing for A Single Population

According to the most recent hearings on Capital Hill, young adult as from the age of 19 to 23 have an average credit card debt of $4,100.  A random sample of 50 from this population were selected and their average credit card debt was $4,360.  Assume the standard deviation foe this debt is $1,200.  Using α =0.05  answer the following:

a.      Does the sample provide enough evidence to challenge these findings?

b.      Determine the p-value for this test.

Answer 1