Alright, let's solve this problem step by step. We have 7518 and 2031 and we're adding them together.

Step 1: We'll start by adding the digits 8 & 1 in column 1 and get 9.

Step 2: We'll start by adding the digits 1 & 3 in column 2 and get 4.

Step 3: We'll start by adding the digits 5 & 0 in column 3 and get 5.

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

So, 7518 + 2031 = 9549.

