Melanie uses 9.4 pints of white paint and blue paint to paint her bedroom walls. 4 5 of this amount is white paint, and the rest is blue paint. How many pints of blue paint did she use to paint her bedroom walls?

She used 4.9 pints of blue paint.

Explanation:

The total amount of paint that Melanie used is 9.4 pints (white and blue).

Blue Paint + White Paint = 9.4 pints.

However, we know that 4.5 of the total amount is white, thus, we can substitute in the expression we just wrote earlier:

Blue Paint + 4.5 = 9.4 pints

Blue Paint = 9.4 pints - 4.5 pints

Blue Paint = 4.9 pints.

Therefore, she used 4.9 pints of blue paint for her bedroom walls.