Let's break this down. We're going to add 5752 and 3123 together.

Step 1: We'll start by adding the digits 2 & 3 in column 1 and get 5.

Step 2: We'll start by adding the digits 5 & 2 in column 2 and get 7.

Step 3: We'll start by adding the digits 7 & 1 in column 3 and get 8.

Step 4: We'll start by adding the digits 5 & 3 in column 4 and get 8.

So, 5752 + 3123 = 8875.

