Let's solve this addition problem. We have 7541 and 2122, and we need to add them together.

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

Step 2: We'll start by adding the digits 4 & 2 in column 2 and get 6.

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

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

So, 7541 + 2122 = 9663.

