The food service at Goldey-Beacom College provides lunch and dinner for the students Monday through Friday. The food-service manager would like to forecast the sales for each day of the following week to ensure she has enough employees staffing the counter. The following data show the daily sales, in dollars, for the last three weeks. These data can also be found in the Excel file cafeteria.xlsx.

Daily Sales ($)

Day Week 1 Week 2 Week 3 Monday 657 718 728 Tuesday 563 561 550 Wednesday 726 740 809 Thursday 539 502 523 Friday 530 587 633

a. Construct a graph showing the food service’s daily sales over time.

b. Forecast the sales for each day next week using multiplicative decomposition.

c. Interpret the meaning of the seasonal components.

d. Calculate the MAD for this forecast.

AppendixLO1