Let be the amount (in quarts) of blue paint used in the mix, and the amount of white paint. For the desired shade, there are 1.5 qt of blue paint for every 5 qt of white, so that .
1 gallon = 4 quarts, so 16.25 gal = 65 qt. We want this amount of the final mixed paint, so that .
Subsituting into this equation gives us
so we need to use 50 qt of blue paint and 15 qt of white paint (since 65 - 50 = 15).
we know the blue and white paints are on a 1.5 : 5 ratio, thus, if we have a total of 16.25 gallons of paint to be split along that ratio, we can simply divide 16.25 by (1.5+5) and distribute accordingly.
its actually 13 1/3
because it just is