9/10 minis what equals 1/5?

7/10

Step-by-step explanation:

Set up an equation to solve the problem

1/5 = 9/10 - x

Lets make them all have a common denominator

1/5 = 2/10

Subtract the 9/10

2/10 = 9/10 - x

- 9/10 - 9/10

-7/10 = - x

Since - x equals - 7/10, that means positive x equals 7/10

The answer then comes out to:

x = 7/10