Not to worry, we've got 81 and 427. Let's get to adding them!

Step 1: We'll start by adding the digits 1 & 7 in column 1 and get 8.

Step 2: We'll start by adding the digits 8 & 2 in column 2 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 0 & 4 in column 3 and get 5.

So, 81 + 427 = 508.

