Okay, we are tasked with adding 73 and 623. Let's begin!

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

Step 2: We'll start by adding the digits 7 & 2 in column 2 and get 9.

Step 3: We'll start by adding the digits 0 & 6 in column 3 and get 6.

So, 73 + 623 = 696.

