Let's break this down. We're going to add 203 and 5370 together.

Step 1: We'll start by adding the digits 3 & 0 in column 1 and get 3.

Step 2: We'll start by adding the digits 0 & 7 in column 2 and get 7.

Step 3: We'll start by adding the digits 2 & 3 in column 3 and get 5.

Step 4: We'll start by adding the digits 0 & 5 in column 4 and get 5.

So, 203 + 5370 = 5573.

