Question

Genevieve uses 7.7 pints of blue paint and white paint to paint her bedroom walls. 1 4 of this amount is blue paint, and the rest is white paint. How many pints of white paint did she use to paint her bedroom walls?

Answer 1

She used 5.775 pints of white paint to paint her bedroom walls.

Explanation:

This question can be solved using a system of equations.

I am going to say that:

x is the amount of white paint used.

y is the amount of blue paint used.

7.7 pints of blue paint and white paint to paint her bedroom walls.

This means that
`x + y = 7.7`

1/4 of this amount is blue paint, and the rest is white paint.

The rest is 1-(1/4) = 3/4. That is, the amount of white paint is the triple of the amount of blue paint. That is,
`y = 3x`, or
`x = (y)/(3)`

Replacing in the first equation:

`x + y = 7.7`

`(y)/(3) + y = 7.7`

`(y + 3y)/(3) = 7.7`

`4y = 3*7.7`

`y = (3*7.7)/(4)`

`y = 5.775`

She used 5.775 pints of white paint to paint her bedroom walls.