Not to worry, we've got 335 and 943. 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 3 & 9 in column 3 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

So, 335 + 943 = 1278.

