Delfonte’s Restaurant is a popular Italian eatery in the Bay Area in northern California. Recently, there has been a dispute among the wait staff regarding the amount of tips waiters receive on the lunch shift and on the dinner shift. Before making any adjustments in schedules or other policies, the restaurant manager wants to estimate the difference in the average tips earned by waiters on the lunch schedule and on the dinner schedule. To do this, she has randomly selected 40 tip reports for lunch servers over the past year and 50 tip reports from dinner servers.

The following results were observed:

Lunch Dinner Mean Tips $62.40 $102.50 St. Dev. Tips $11.30 $12.33 Assuming equal population variances, develop and interpret a 95% confidence interval estimate for the difference between the population mean tips earned by lunch servers and by dinner servers.