Not to worry, we've got 2553 and 1215. Let's get to adding them!

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 5 & 1 in column 2 and get 6.

Step 3: We'll start by adding the digits 5 & 2 in column 3 and get 7.

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

So, 2553 + 1215 = 3768.

