Not to worry, we've got 8511 and 8454. Let's get to adding them!

Step 1: We'll start by adding the digits 1 & 4 in column 1 and get 5.

Step 2: We'll start by adding the digits 1 & 5 in column 2 and get 6.

Step 3: We'll start by adding the digits 5 & 4 in column 3 and get 9.

Step 4: We'll start by adding the digits 8 & 8 in column 4 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

So, 8511 + 8454 = 16965.

