Question

A delivery truck is transporting boxes of two sizes: large and small. The combined weight of a large box and a small box is 70 pounds. The truck is transporting 60 large boxes and 65 small boxes. If the truck is carrying a total of 4300 pounds in boxes, how much does each type of box weigh?

Answer 1

x = large boxes and y = small boxes

x + y = 70.....x = 70 - y
60x + 65y = 4300

60(70 - y) + 65y = 4300
4200 - 60y + 65y = 4300
5y = 4300 - 4200
5y = 100
y = 100/5
y = 20 <=== the small boxes weigh 20 lbs

x + y = 70
x + 20 = 70
x = 70 - 20
x = 50 <== and the large boxes weigh 50 lbs