Goal Programming Answers:

1)  Note that since the demand goal stated "meet the demand as much as possible" production deviation either above or below demand is considered undesirable for both types of televisions. Also note that all apparent "hard" constraints are superceded by goal constraints.
 
Let: C = # of color televisions produced

B = # of black and white televisions produced

ds+ = deviation above skilled labor utilization target

ds- = deviation below skilled labor utilization target

du+ = deviation above unskilled labor utilization target

du- = deviation below unskilled labor utilization target

dc+ = deviation above color television demand target

dc- = deviation below color television demand target

db+ = deviation above black and white television demand target

db- = deviation below black and white television demand target

do+ = deviation above unskilled labor overutilization target

do- = deviation below unskilled labor overutilization target

Minimize Z = 
ds+ + du- + dc+ + dc- + db+ + db- + do+

s.t. 
10 C + 5 B - ds+ + ds-
=
100
(Skilled use goal)

100 C + 150 B - du+ + du-
=
1,500
(Unskilled use goal)
 
C - dc+ + dc-
=
70
(Color demand goal)
 
B - db+ + db-
=
45
(B&W demand goal)
 
du+ - do+ + do-
=
100
(Unskilled overuse goal)

where: 
C, B, ds+,  ds-, du+, du-, dc+, dc-, db+, db-, do+, do- > 0 and
C, B are integer

Excel Spreadsheet Solutions


2)  Note that an arbitrarily high number has been chosen for the RHS of the final goal constraint to "maximize the audience points." Also note that all apparent "hard" constraints are superceded by goal constraints.
 
Let: R = # of local radio spots purchased

T = # of local television spots purchased

N = # of newspaper ads purchased

db+ = deviation above budget target

db- = deviation below budget target

dc+ = deviation above television contract target

dc- = deviation below television contract target

dp+ = deviation above newspaper policy target

dp- = deviation below newspaper policy target

da+ = deviation above audience points target

da- = deviation below audience points target

Minimize Z = 
10 db+ + 6 dc- + 3 dp+ + da-

s.t. 
100 R + 500 T + 200 N - db+ + db-
=
200,000
(Budget goal)

500 T - dc+ + dc-
=
30,000
(TV contract goal)
 
200 N - dp+ + dp-
=
50,000
(Newspaper goal)
 
30 R + 150 T + 150 N - da+ + da-
=
1,000,000
(Audience goal)

where: 
R, T, N, db+,  db-, dc+, dc-, dp+, dp-, da+, da- > 0 and 
R, T, N are integer

Excel Spreadsheet Solutions


3)  Note that a heuristic is employed in assigning objective coefficients in order to prioritize goal compliance. The variable representing the deviation with the lowest priority is assigned a weight of "1" and the weights are increased by a factor of 10 for each successively more important goal. The resulting solution, however, does not allow compliance with goal 3 before that for goal 4. There is no feasible solution that allows compliance with goal 3 if goals 1 and 2 are both satisfied. Also note that only the total acres available for building remains as a "hard" constraint.
 
Let: S = # of single-familiy homes built

C = # of deluxe condominiums built

A = # of apartments built

D = # of acres of land not used for building

df+ = deviation above families housed target

df- = deviation below families housed target

dt+ = deviation above tax base target

dt- = deviation below tax base target

ds+ = deviation above city services tax target

ds- = deviation below city services tax target

dp+ = deviation above park set-aside target

dp- = deviation below park set-aside target

Minimize Z = 
1,000 df- + 100 dt- + 10 ds+ + dp-

s.t. 
.25 S + .2 C + .125 A + D
=
50
(Acres available)






S + 4 C + 6 A - df+ + df-
=
500
(Families goal)

5 S + 10 C + 15 A - dt+ + dt-
=
500
(Tax base goal)
 
4 S + 8 C + 10 A - ds+ + ds-
=
250
(City service tax goal)
 
D - dp+ + dp-
=
5
(Park goal)

where: 
S, C, A, D, df+,  df-, dt+, dt-, ds+, ds-, dp+, dp- > 0 and 
S, C, A are integer

Excel Spreadsheet Solutions


4)
Let:
X1 =
# of tons of plywood produced
 
X2 =
# of tons of chipboard produced
 
X3 =
# of tons of pulp produced
 
X4 = {
1 if plywood is produced
0 if otherwise
 
X5 = {
1 if chipboard is produced
0 if otherwise
 
X6 = {
1 if pulp is produced
0 if otherwise

dp+ =
deviation above profit target

dp- =
deviation below profit target

dg+ =
deviation above glue requirement target

dg- =
deviation below glue requirement target

da+ =
deviation above additive requirement target

da- =
deviation below additive requirement target

Minimize Z = 
5 dp- + dg+ + da+

s.t.
.95 X1 + .91 X2 + .86 X3
<
15,000
(Wood available)
 
X1 - 10,000 X4
<
0
(Ply demand)
 
X2 - 5,000 X5
<
0
(Chip demand)

X3 - 5,000 X6
<
0
(Pulp demand)






10 X1 + 9 X2 + 6 X3 - 50,000 X4 - 25,000 X5 - 2,000 X6 - dp+ + dp-
=
70,000
(Profit goal)

.05 X1 + .05 X2 - dg+ + dg-
=
500
(Glue goal)

.04 X2 + .14 X3 - da+ + da-
=
500
(Additives goal)

where: 
X1, X2, X3, X4, X5, X6, dp+, dp-, dg+, dg-, da+, da- > 0, 
X1, X2 are integer, and
X4, X5, X6 are binary

Excel Spreadsheet Solutions


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