A punch recipe says to mix 4 cups of pineapple juice, 8 cups of orange juice, and 12 cups seltzer to make 18 servings. how many cups do you need of each to make 108 servings

Answer 1

108/18 = 6
so just multiply all the amounts by 6.

Answer 2

108 / 18 = 6

Multiply each ingredient for 18 servings by 6.
6 * 4 = 24
etc.