Here we go! We're going to add 8791 and 2081 together.

Step 1: We'll start by adding the digits 1 & 1 in column 1 and get 2.

Step 2: We'll start by adding the digits 9 & 8 in column 2 and get 17.
We'll write down the last digit 7 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 7 & 0 in column 3 and get 8.

Step 4: We'll start by adding the digits 8 & 2 in column 4 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

So, 8791 + 2081 = 10872.

