Question

Connelly has 1 / 4 of a cup of water. Ryan has 2 / 5 of a cup of water. Grayson has 0.4 less than 2 times Connelly's amount of water.
Write the expression that can be used to find how much water Ryan and Grayson have together.

Answer 1

We will make ''X'' the result that we are searching for
and ''Y'' how much water Grayson has 

So we have :  X = Y + 2/5

and : Y = 2/4 - 0.4 = 1/2 - 4/10 = 1/10

So X = 1/10 + 2/5 = 5/10 = 1/2 0f a cup