A delivery truck is transporting boxes of two sizes: large and small. The combined weight of a large box and small box is 75 pounds. The truck is transporting 70 large boxes and 60 small boxes. If the truck is carrying a total of 4900 pounds in boxes, how much does each type of box weigh?

Small box weighs 35 pounds.

Large box weighs 40 pounds.

Step-by-step explanation:

Let the weight of a small box be x and the weight of the large box be y pound:

x + y = 75

60x + 70y = 4900

6x + 7y = 490 ... A

Mulyiply the first equation by 6:

6x + 6y = 450 ... B

Subtract equation A - equation B:

y = 40 so the large box weighs 40 pounds.

Substitute y = 40 into x + y = 75:

x + 40 = 75

x = 75 - 40

x = 35.