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Question 1 (10 marks)
A cobbler makes three types of shoes: stiletto, casual and park. Each pair of stiletto takes 8
hours to fabricate, 5 hours to sand and 6 hours to couple. Each pair of casual takes 6 hours to
fabricate, 4 hours to sand and 2 hours to couple. Each pair of park requires 5 hours of
fabrication, 2 hours of sanding and 4 hours of coupling. The cobbler has 96 hours for
fabrication, 44 hours for sanding and 58 hours for coupling. The profit margins are N$38 per
pair of stiletto, N$26 per pair of casual and N$22 per pair of park. Model this information into a
linear programming problem. Declare your variables unambiguously and name the constraints.
DO NO SOLVE.
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Question 2 (13 marks)
Solve the following linear programming model graphically:
Minimize H = I Sa+ l 2b
Subject to 6a + 6b 36
3a+9b 27
b~3
a~IO
a; b 0
Use 1cm to I unit for each of the axes.
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Question 3 (28 marks)
Consider the following L-P model:
Minimize C = 40a + 60b + 48d
Subject to 5a + 3b + 4d 7
2a + l 2b + 8d 21
a~O;b ~O;d~O
3.1 Write down the dual of the model.
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3.2 Solve the dual model.
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3.3 Suppose the solution of the dual model is x =4; y =4; t, = 12; t2 = 0; t3 =0; C =112.
Use this solution to determine the solution ofthe given primal model.
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