Linear Equation Word Problem

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 85 pounds. The truck is transporting 55 large boxes and 70 small boxes. If the truck is carrying a total of 5125 pounds in boxes, how much does each type of box weigh?

Answer 1

Sharie-

Let x = wt. of large box, y = wt. of small box

We know that the combined weight is 85, so

x + y = 85

 

There are 55 large boxes on the truck , so 55x is the weight of the large boxes.  There are 70 small boxes, so the weight of the small boxes is 70 y.  The total weight is 5125, so

55x + 70 y = 5125

x+y = 85,

x = 85 - y   Substitute

55(85-y) + 70 y = 5125

4675 - 55y + 70 y = 5125

4675 + 15 y = 5125

15 y = 450

 

Solve for y, substitute back and solve for x.

Mary