Okay, we are tasked with adding 6206 and 3689. Let's begin!

Step 1: We'll start by adding the digits 6 & 9 in column 1 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 8 in column 2 and get 9.

Step 3: We'll start by adding the digits 2 & 6 in column 3 and get 8.

Step 4: We'll start by adding the digits 6 & 3 in column 4 and get 9.

So, 6206 + 3689 = 9895.

