1. Multiply the amount of iced tea mix by 1/3 to get the amount of water.
Step-by-step explanation:
As seen in the graph, for every 1 cup of water, 3 tablespoons of the mix are needed.
3 * X = 1
X= 1/3
2. Use the equation y=3x
X=18 , y=cups of water needed
Y= 3*18
Y= 54 cups of water are needed