algebra please help
posted by mark on .
how much of 12.5% of skylite red pigment needs to be mixed with 20% macintosh red pigment to get a 17% red pigment?

If the fraction of "skylight" is x and the fraction of the "macintosh" is 1x, the fraction of red pigment contained in the mixture will be
0.125 x + 0.20 (1x) = 0.17
Solve for x.
0.03 = 0.075x
x = 0.4 = skylight fraction
(1x) = 0.60 = macintosh fraction