Question

CCN and ActMedia provided a television channel targeted to individuals waiting in supermarket checkout lines. The channel showed news, short features, and advertisements. The length of the program was based on the assumption that the population mean time a shopper stands in a supermarket checkout line is 8.5 minutes. A sample of actual waiting times will be used to test this assumption and determine whether actual mean waiting time differs from this standard.

b. A sample of 150 shoppers showed a sample mean waiting time of 9.4 minutes. Assume a population standard deviation of 3.

z value=?

p-value =?

d.  Compute a 99% confidence interval for the population mean. Does it support your conclusion?

(?,?) (to 2 decimals)

Answer 1

d) 99 % confidence interval;

Population mean 8.5 does not fall in above interval hence we reject the null hypothesis. Hence it supports the conclusion.

Hope this will help you. Thank you :)