Question

Step by step plz

Freight car loadings over a 10-week period at a busy port are as follows:

Week	Number
1	220
2	245
3	280
4	275
5	300
6	310
7	362
8	360
9	402
10	400

Develop forecast from week 5 to week 10 by using 4-week moving average.

Find the MAD for this forecasting method.

Please round your answer to 4 decimal places if necessary.

Answer 1

The 4-month moving average forecasts are calculated in the table below:

Week	Number(A)	Forecasts(F)	Absolute Error =|A-F|
1	220	-	-
2	245	-	-
3	280	-	-
4	275	-	-
5	300	(220 + 245 + 280 + 275)/4 = 255	|300-255| = 45
6	310	(245 + 280 + 275 + 300)/4 = 275	|310-275| = 35
7	362	(280 + 275 + 300 + 310)/4 = 291.25	|362-291.25| = 70.75
8	260	(275 + 300 + 310 + 362)/4 = 311.75	|260-311.75| = 51.75
9	402	(300 + 310 + 362 + 260)/4 = 308	|402-308| = 94
10	400	(310 + 362 + 260 + 402)/4 = 333.5	|400-333.5| = 66.5
Total	-	-	363

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