Answer:
- 55 boxes of 50 pounds
- 65 boxes of 15 pounds
Explanation:
It works well to define a variable that represents the number of the heaviest boxes. Let's call that x. Then the number of lighter boxes is (120 -x), and the total weight is ...
50x +15(120 -x) = 3725
35x +1800 = 3725 . . . . . . eliminate parentheses
35x = 1925 . . . . . . . . . . . . subtract 1800
x = 1925/35 = 55 . . . . . . . .divide by 35; the number of 50-lb boxes
120 -x = 65 . . . . . . . . . . . . .the number of 15-lb boxes
The truck is carrying 55 50-lb boxes and 65 15-lb boxes.