Let's get this math done. We have 7503 and 115 and we're going to add them all together.

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

Step 2: We'll start by adding the digits 0 & 1 in column 2 and get 1.

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 & 0 in column 4 and get 7.

So, 7503 + 115 = 7618.

