Addition and Subtraction - Balance Equations - within 100

Consider the equation:

91 – __ = 7 + 74

Let's identify the missing number that makes the equation true.

To identify the missing number, first we need to add 7 + 74:

91 – ? = 7 + 74

91 – ? = 81

Now, to find the missing number we need to calculate 91 – 81.
 

91 – 81 = 10
 

91 – 10 = 7 + 74

So, the missing number is 10.