No problem, let's work through this together. We're starting with 7484 and 2404 and adding them all up.

Step 1: We'll start by adding the digits 4 & 4 in column 1 and get 8.

Step 2: We'll start by adding the digits 8 & 0 in column 2 and get 8.

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

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

So, 7484 + 2404 = 9888.

