Typo- that second "PR" should be "RP".

Only that xThe constraints, I think, would be: 1/3x_{1}+ 1/2x_{2}<= 60 (maximum amount of peanuts)

2/3x_{1}+ 1/2x_{2}<= 90 (maximum amount of raisins)

x_{1}+ x_{2}<= 150 (maximum amount of mix packages)

Anything else?_{1}+ x_{2}>0 0.

Yes, subtract off the costs. If you use (1/3)xThe optimization equation is what I can't quite figure out, though. I figure I could just write it F = 2.9x_{1}+ 2.55x_{2}--> max. But this formula would calculate revenue maximisation, not profit. So any way to make the formula take costs into account as well?_{1}kg of peanuts in RP and (1/2)x_{2}kg of peanuts in Pr, and each kilogram of peanuts cost £0.6 then you need to subtract .6((1/3)x_1+ (1/2)x_2) from the profit. Do the same for the raisins and packages.

Great. But "point of maximization" ofI did draw the graph (the feasibility region) and point of maximization does in fact show (90;60), which should be the correct answer. Point is, how to use the optimization equation to calculate the comparative values of all the corner points of the feasibility region?what. The point you want should be the vertex where the profit is largest and you are saying you do not know how to find that.