Hw2 Slution

Month
Sales
F M A M J J A S
20
0
2. a.

b. 1) | | t | Y | tY | From Table 3–1 with n = 7, t = 28, t2 = 140 | | | 1 | 19 | 19 | | | | 2 | 18 | 36 | | | | 3 | 15 | 45 | | | | 4 | 20 | 80 | | | | 5 | 18 | 90 | | | | 6 | 22 | 132 | | | | 7 | 20 | 140 | | | | 28 | 132 | 542 | | For Sept., t = 8, and Yt = 16.86 + .50(8) = 20.86 (000)

2)
Solutions (continued) 3) | | Month | Forecast = | F(old) | + | .20[Actual – F(old) ] | | | April | 18.8 = | 19 | + | .20[ 18 – 19 ] | | | May | 18.04 = | 18.8 | + | .20[ 15 – 18.8 ] | | | June | 18.43 = | 18.04 | + | .20[ 20 – 18.04 ] | | | July | 18.34 = | 18.43 | + | .20[ 18 – 18.43 ] | | | August | 19.07 = | 18.34 | + | .20[ 22 – 18.34 ] | | | September | 19.26 = | 19.07 | + | .20[ 20 – 19.07 ] | 4) 20 5) .6 (20) + .3(22) + .1(18) = 20.4 c. Probably 5 month moving average because the data appear to vary around an average of about 19 [18.86]. d. Sales are reflective of demand (i.e., no stockouts or backorders occurred). 7. | a. | t | Y | t*Y | t2 | | 1 | 220 | 220 | 1 | | 2 | 245 | 490 | 4 | | 3 | 280 | 840 | 9 | | 4 | 275 | 1,100 | 16 | | 5 | 300 | 1,500 | 25 | | 6 | 310 | 1,860 | 36 | | 7 | 350 | 2,450 | 49 | | 8 | 360 | 2,880 | 64 | | 9 | 400 | 3,600 | 81 | | 10 | 380 | 3,800 | 100 | | 11 | 420 | 4,620 | 121 | | 12 | 450 | 5,400 | 144 | | 13 | 460 | 5,980 | 169 | | 14 | 475 | 6,650 | 196 | | 15 | 500 | 7,500 | 225 | | 16 | 510 | 8,160 | 256 | | 17 | 525 | 8,925 | 289 | | 18 | 541 | 9,738 | 324 | | 171 | 7001 | 75,713 | 2109 |

b. F = 208.444 + (19)(20) = 588.444 F = 208.444 + (19)(21) = 607.444 The forecasted demand for week 20 and 21 is 588.444 and 607.444 respectively.
Solutions (continued) c. weeks