Kevin and Doreen each made a fruit salad. The amounts of ingredients they have are shown. Kevin used all of the​ strawberries, blueberries, and melon to make his fruit salad. Doreen made 2 cups of fruit salad containing all of the​ bananas, peaches and apples. How much fruit salad did Kevin​ make? How much more fruit salad did Doreen make than​ Kevin?

The first thing you should do for this case is to graph the data you have in the statement to see the relationship between grapes and blueberries.

The function represented by the table is

y = 0.25x

Then, as Mandie is making 15 glasses of fruit salad, we have:

y + x = 15

We have two equations and two unknowns that we must solve.

y = 0.25x

y + x = 15

Resolving

For x:

0.25x + x = 15

1.25x = 15

x = 15 / 1.25 = 12

For y:

y = 0.25x = 0.25 (12) = 3

Answer

The ratio of grapes to blueberries she should use is 12: 3