Not to worry, we've got 306 and 9103. Let's get to adding them!

Step 1: We'll start by adding the digits 6 & 3 in column 1 and get 9.

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

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

Step 4: We'll start by adding the digits 0 & 9 in column 4 and get 9.

So, 306 + 9103 = 9409.

