Let's break this down. We're going to add 6013 and 2806 together.

Step 1: We'll start by adding the digits 3 & 6 in column 1 and get 9.

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

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

Step 4: We'll start by adding the digits 6 & 2 in column 4 and get 8.

So, 6013 + 2806 = 8819.

