Alright, let's solve this problem step by step. We have 2125 and 7538 and we're adding them together.

Step 1: We'll start by adding the digits 5 & 8 in column 1 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 2 & 3 in column 2 and get 6.

Step 3: We'll start by adding the digits 1 & 5 in column 3 and get 6.

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

So, 2125 + 7538 = 9663.

