Okay, we are tasked with adding 5220 and 4012. Let's begin!

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

Step 2: We'll start by adding the digits 2 & 1 in column 2 and get 3.

Step 3: We'll start by adding the digits 2 & 0 in column 3 and get 2.

Step 4: We'll start by adding the digits 5 & 4 in column 4 and get 9.

So, 5220 + 4012 = 9232.

