Here we go! We're going to add 809 and 102 together.

Step 1: We'll start by adding the digits 9 & 2 in column 1 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 0 in column 2 and get 1.

Step 3: We'll start by adding the digits 8 & 1 in column 3 and get 9.

So, 809 + 102 = 911.

