Question

A store received a delivery that consists of x boxes that weigh 30 pounds each and y boxes that weigh 20 pounds each. There are 64 total boxes in the delivery and they have a combined weight of 1400 pounds.

enter the number of boxes in the delivery that weigh 20 pounds.

Answer 1

Let the number of 30 pound boxes represented by =x

Let the number of 20 pound boxes be represented by =y

As given, there are 64 boxes so equation is:

`x+y=64` or
`x=64-y` ..... (1)

Total weight is 1400 pounds so equation becomes

`30x+20y=1400` ...............(2)

Plug in the value of
`x=64-y` in 2nd equation

`30(64-y)+20y=1400`

`1920-30y+20y=1400`

`10y=520`

`y=52` and
`x=64-52=12`

Hence, the number of boxes for delivery that weigh 20 pounds is 52.