Subtract within 100

The first instance of  exercise is in the Early Math Math Mission. This exercise introduces users to subtraction with carrying.

Types of Problems
There is only one type of problem in this exercise:
 * 1) Subtracting with carrying: This type of problem introduces users to subtracting numbers with carrying. There are no hints for this type of problem, however, it isn't too difficult, as the numbers are all under 100.

Strategies
These problems are quite simple if you remember your basic subtraction! Subtract the numbers in the right column first and then carry the remainder (if any) over to the left. Then simplify.