Question

3. A company is interested in estimating the costs of lunch in their cafeteria. After surveying employees, the staff calculated that a 95% confidence interval for the mean amount of money spent for lunch over a period of six months is ($780, $920). Now the organization is trying to write its report and considering the following interpretations. Comment on each.

   1. 95% of all employees pay between $780 and $920 for lunch.

   2. 95% of the sampled employees paid between $780 and $920 for lunch.

   3. We’re 95% sure that employees in this sample averaged between $780 and $920 for lunch.

   4. 95% of all samples of employees will have average lunch costs between $780 and $920.

   5. We’re 95% sure that the average amount all employees pay for lunch is between $780 and $920.

Answer 1

Given that, a 95% confidence interval for the mean amount of money spent for lunch over a period of six months is ($780, $920).

The correct Interpretation of this interval is :

We are 95% sure (confident) that the average amount all employees pay for lunch is between $780 and $920.