Okay, we are tasked with adding 7121 and 2276. Let's begin!

Step 1: We'll start by adding the digits 1 & 6 in column 1 and get 7.

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

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

Step 4: We'll start by adding the digits 7 & 2 in column 4 and get 9.

So, 7121 + 2276 = 9397.

