Here we go! We're going to add 8641 and 5286 together.

Step 1: We'll start by adding the digits 1 & 6 in column 1 and get 7.

Step 2: We'll start by adding the digits 4 & 8 in column 2 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 6 & 2 in column 3 and get 9.

Step 4: We'll start by adding the digits 8 & 5 in column 4 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 8641 + 5286 = 13927.

