Let's get this math done. We have 1285 and 3403 and we're going to add them all together.

Step 1: We'll start by adding the digits 5 & 3 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 2 & 4 in column 3 and get 6.

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

So, 1285 + 3403 = 4688.

