Not to worry, we've got 9669 and 5109. Let's get to adding them!

Step 1: We'll start by adding the digits 9 & 9 in column 1 and get 18.
We'll write down the last digit 8 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 6 & 0 in column 2 and get 7.

Step 3: We'll start by adding the digits 6 & 1 in column 3 and get 7.

Step 4: We'll start by adding the digits 9 & 5 in column 4 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

So, 9669 + 5109 = 14778.

