4. Linear programming.

A chicken farmer wants to feed chickens the minimum daily requirement of nutrients A, B and C at lowest costs. Daily requirements are 28 units of A, 20 of B and 12 of C. Feed grain X contains 1A, 1B and 1C, while feed grain Y contains 2A, 1B and C. The price of X = $1.25 and the price of Y = $2.00. The problem is to find the least-cost combination of X and Y that fulfills the minimum nutrient requirements.

This is an LP and the mathematical expression for the problem is:

Minimize Z = 1.25 x + 2 y

s.t. 1 x + 2 y 28 (A nutrient requirement)

1 x + 1 y 20 (B nutrient requirement)

1 x + y 12 (C nutrient requirement)

x, y 0

Use the solver in Excel to set up and solve the LP problem.

What happens if the price of X rises from $1.25 to $1.80? What happens if it rises to $2.00?

I need the process and result.