Question

A delivery truck is transporting boxes of two sizes: large and small. The large boxes weigh 40 pounds each, and the small boxes weigh 20 pounds each. There

are 125 boxes in all. If the truck is carrying a total of 3900 pounds in boxes, how many of each type of box is it carrying?

Answer 1

large box 70, small 55
x+y=125
40x+20y=3900
y=125-x
40x+20(125-x)=3900
40x+2500-20x=3900
20x=1400
x=70
125-70=y
y=55