How many cups of sorbet are used in 8 cups of punch?
punch recipe
ginger ale- 40%
orange juice- 25% pineapple juice- 20% sorbet- 15%

Given that 8 cups equals 100% of this punch, we need to figure out how many coups does 15% of sorbet make. This is how we do this:
8 (cups) : 100% (the entire amount of punch) = x (the number of sorbet cups) : 15% (the amount of sorbet used)
So:
x : 15 = 8 : 100
100x = 15 * 8
100x = 120
x = 1.2
The answer is 1.2 cups of sorbet were used in this punch.