The last four months of sales were 8 10 15 and 9 units The l

The last four months of sales were 8, 10, 15, and 9 units. The last four forecasts were 5, 6, 11, and 12 units. The MAD (also known as MAE) is

            a.         2                      b.   -10                         c.         3.5                   d.      9

            e.         12.5

Solution

Sol:

MAD=3.5

find actual-forecast

take modulus of (actual-forecast)

take average for above.