We have numbers 8502 and 4304. Let's start adding them together.

Step 1: We'll start by adding the digits 2 & 4 in column 1 and get 6.

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

Step 3: We'll start by adding the digits 5 & 3 in column 3 and get 8.

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

So, 8502 + 4304 = 12806.

