Answer: 7.5 quarts of yellow paint
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Work Shown:
(5 yellow)/(6 red) = (x yellow)/(9 red)
5/6 = x/9
5*9 = 6*x
45 = 6x
6x = 45
x = 45/6
x = (15*3)/(2*3)
x = 15/2
x = 7.5
You need 7.5 quarts of yellow paint if you want to mix with 9 quarts of red.
Note: the decimal 7.5 is the same as the mixed number 7 & 1/2.
