Question

How do I do this problem

Answer 1

The Ross family used it for 15 hours

The Watson family used it for 20 hours

Explanation:

We can rewrite this word problem using variables.

`(x*40)+(y*20)=1000` and
`x+y=35`

Now we can split 35 between x and y. Since 35 can't be split into a whole number, I have split it into 17 and 18

(17*40) + (18*20) = 1040

This is close but 40 too much. Since this is 40 off, we need to move 2 more hours to the Watson family.

(15*40) + (20*20) = 1000

This means -

The Ross family used it for 15 hours

The Watson family used it for 20 hours