Question on constraints

Question

Using the following information write the constraints. There should be five total. 

• You can tutor no more than 18 hours per week
• The tutoring center requires that you tutor math at least 4 hours per week
• Since the demand for math tutors is greater than the demand for chemistry tutors you must spend at least twice the number of hours tutoring math as you do tutoring chemistry

The objective function is z= 24x + 20y

Answer 1

4<x+y<18,

x>2y

z=24x+20y

check 4 points (4,0), (18,0), (4,8), (18,36)

24(18)+20(36) = 1152

assuming x=math hours, y= chemistry hours

it helps to sketch a graph

It's a linear programming problem

but same basic answer if you switch math & chemistry

then

z= 24(36)+20(18) = 1224