In a seafood stew, Erin wants to use lobster, crab, and shrimp. She wants one part lobster, two parts crab, and three parts shri
mp. lobster cost $20 per pound, crab cost $15 per pound, and shrimp cost $10 per pound. Erin has $40 to spend on the seafood mix. The equation 20x + 15(2x) + 10(3x) = 40 models the pounds, x. How many pounds of the seafood mix can Erin buy?