You have $15.00 and each shirt you bought was $4.25
$4.25x3=$12.75
$15.00-$12.75= $2.25
So your shorts were $2.25
Answer:
a) Objective function (minimize cost):

Restrictions
Proteins per pound: 
Vitamins per pound: 
Non-negative values: 
b) Attached
c) The optimum solution (minimum cost) is 0 pounds of ingredient A and 0.75 pounds of ingredient B. The cost is $0.15 per ration.
d) The optimum solution changes. The cost is now 0 pounds of ingredient A and 0.625 pounds of ingredient B. The cost is $0.125 per ration.
Step-by-step explanation:
a) The LP formulation for this problem is:
Objective function (minimize cost):

Restrictions
Proteins per pound: 
Vitamins per pound: 
Non-negative values: 
b) The feasible region is attached.
c) We have 3 corner points. In one of them lies the optimal solution.
Corner A=0 B=0.75

Corner A=0.5 B=0.5

Corner A=0.75 B=0

The optimum solution (minimum cost) is 0 pounds of ingredient A and 0.75 pounds of ingredient B. The cost is $0.15 per ration.
d) If the company requires only 5 units of vitamins per pound rather than 6, one of the restrictions change.
The feasible region changes two of its three corners:
Corner A=0 B=0.625

Corner A=0.583 B=0.333

Corner A=0.75 B=0

The optimum solution changes. The cost is now 0 pounds of ingredient A and 0.625 pounds of ingredient B. The cost is $0.125 per ration.
The answer should be 3.8
You can find this by dividing the total descent by the minutes the descent took
7x + 2y = 48
7x + (2x3) =48
7x + 6 = 48
7x = 48 - 6
7x = 42
--> x = 6