Okay, we are tasked with adding 7115 and 1223. Let's begin!

Step 1: We'll start by adding the digits 5 & 3 in column 1 and get 8.

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

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 & 1 in column 4 and get 8.

So, 7115 + 1223 = 8338.

