Hey everyone. I cant figure out how to set this word problem up for the simplex Big M method. Any help would be greatly appreciated!

A company produces two types of mixes, Mix R and Mix D

Mix R has at least 20% nuts

Mix R has at most 40% Bolts

Mix D has at least 30% nuts

Mix D has at most 40% bolts.

The company has available to it:

1200 pounds of screws

750 pounds of nuts

1500 pounds of bolts

Knowing that the company makes $0.60 dollars per pound of mix D and $0.40 dollars per pound of mix R how many pounds of nuts, bolts and scews should be used to maximise the companies profit.