For every 3 pints of red paint there are 5 pints of white paint

5 + 3 = 8, so there are 8 pints of pint in total in the mixture.

| r | r | r | r |
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| r |w |w |w |


48 ÷ 8 = 6, so there would be 6 diagrams (not that I think you need to draw them all out, but point out that fact).

5 * 6 = 30 pints of red (each diagram holds 5 red pints)
3 * 6 = 18 pints of white (each diagram holds 3 white pints)