Not to worry, we've got 135 and 9043. Let's get to adding them!

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 3 & 4 in column 2 and get 7.

Step 3: We'll start by adding the digits 1 & 0 in column 3 and get 1.

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

So, 135 + 9043 = 9178.

