The medieval spice merchant wants to blend some garlic powder, which costs 38 cents per pound, with 7 pounds of ground pepper, which costs 44 cents per pound, to create a big batch of medieval smelling salt worth exactly 40 cents per pound. How many pounds of the garlic powder should he use? I do know that the value of the garlic powder plus the value of the ground pepper has to equel the value of the smelling salt. And value equals cost per pound times number of pounds. But I still don't know how to work it out. Help!