Answer:
37.5%
Step-by-step explanation:
The amount of paint in the mix can be found from the given information. That can then be used to find the percentage of red paint in the mix.
Of the 20 quarts of original mixture, 25% are red paint. The number of quarts of red paint in that mixture is ...
25% × 20 qt = 5 qt
After 4 quarts of red paint are added, there will be
5 qt + 4 qt = 9 qt . . . . volume of red paint
20 qt + 4 qt = 24 qt . . . . volume of new mixture
The percentage of new mixture that is red paint is the fraction, multiplied by 100%.
[tex]\dfrac{9\text{ qt}}{24\text{ qt}}\times100\% = \dfrac{3}{8}\times100\%=\boxed{37.5\%}[/tex]
37.5% of the new mixture is red paint.
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Additional comment
6 quarts of yellow paint comprise 25% of the new mixture; 9 quarts of water comprise 37.5% of the new mixture.
