Hamburger costs $1.50 per pound and soy costs $1.00 per pound. the school cafeteria uses 50 more pounds of soy than hamburger and spends $350 a week. how much soy does the school use?

Suppose the the school uses x pounds of Hamburger, then the number of pounds of soy is x+50, the cost of Hamburger is 1.50x, the cost of soy is 1.00(x+50), the total cost if 350
1.50x +1.00(x+50)=350
2.50x+50=350
2.50x=300
x=120
120+50=170
so the school uses 120 pounds of Hamburger and 170 pounds of soy