A manufacturer produces two different models: X and Y, of the same product. Model
X makes a contribution of Rs. 50 per unit and model Y, Rs. 30 per unit towards total
profit. Raw materials 1
r and 2r are required for production. At least 18 kg of 1
r and 12
kg of 2r must be used daily. Also at most 34 hours of labour are to be utilized. A
quantity of 2 kg of 1
r is needed for model X and 1 kg of 1
r for model Y. For each of X
and Y, 1 kg of 2r is required. It takes 3 hours to manufacture model X and 2 hours to
manufacture model Y. How many units of each model should be produced to
maximize the profit?