Question

Discuss a situation in your school environment where you needed to make a decision by identifying:

1. State an objective function
2. Decision variables
3. Constraints

Answer 1

I need to purchase food items for the upcoming picnic of the class. A burger comes at $1.5 while a pastry comes for $1.8. I have to minimise the cost as the class has limited budget. The total number of these two items would be at least 140. Further, the quantity of pastries  must be at least 0.7 times the burgers.

Decision variables are X = Number of burgers Y= Number of pastries

The objective function that miniimises the cost is

Min [ 1.5X+1.8Y]

such that

X+Y=>140 ( constraint of quantity)

Y=>0.7X or

Y-0.7X=>0 ( constraint of ratio of two items)

X=>0, Y=>0 ( Non negativity constraints)