11-14 Highland Automotive wishes to forecast the number
of new cars that will be sold next week. The following
table summarizes the number of new cars sold
during each of the past 12 weeks: (PLEASE ANSWER BY USINGEXCEL)
| week | number sold |
| 1 | 22 |
| 2 | 26 |
| 3 | 23 |
| 4 | 27 |
| 5 | 21 |
| 6 | 25 |
| 7 | 28 |
| 8 | 26 |
| 9 | 29 |
| 10 | 29 |
| 11 | 27 |
| 12 | 31 |
(a) Provide a forecast by using a 3-week weighted
moving average technique with weights 5, 3, and
1 (5 = most recent).
(b) Forecast sales by using an exponential smoothing
model with a = 0.45.
(c) Highland would like to forecast sales by using
linear trend analysis. What is the linear equation
that best fits the data?
(d) Which of the methods analyzed here would you
use? Explain your answer.
