Ahab needs to mix 3.5 cups of liquid iced tea concentrate with 3 cups of water to make iced tea. Ahab has 21 cups of iced tea concentrate. How much iced tea can he make?

39 cups

Step-by-step explanation:

If we assume that the 3.5 cups of concentrate make 3.5+3 = 6.5 cups of tea, we can use the proportion ...

6.5/3.5 = x/21

to find the x cups of tea Ahab can make with 21 cups of concentrate.

Multiplying by 21, we get ...

x = 21 (6.5/3.5) = 39

Ahab can make 39 cups of tea.