Let's break this down. We're going to add 2720 and 2003 together.

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

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

Step 3: We'll start by adding the digits 7 & 0 in column 3 and get 7.

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

So, 2720 + 2003 = 4723.

