Answer Key to Question #'s 18, 19, 20, 21 Question #18 Calculate the below: a) Using 3 month moving average, forecast for periods 6-11 b) Using 5 month moving average, forecast for periods 6-11 c) Calculate mean absolute deviation for each period for each forecast method d) Make recommendation on forecast method to use Month 1 2 3 4 Demand 23 24 32 26 53 6 7 8 9 10 11 31 28 32 35 26 24 3 X X X X X 29.67 28.33 30.33 31.67 31.00 28.33 month avg. 5 X X X x X 27.2 28.2 29.8 30.4 30.4 29.00 month avg. a) 3 month moving average