No problem, let's work through this together. We're starting with 6397 and 2399 and adding them all up.

Step 1: We'll start by adding the digits 7 & 9 in column 1 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 9 & 9 in column 2 and get 19.
We'll write down the last digit 9 and carry the 1 to the next column.

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

Step 4: We'll start by adding the digits 6 & 2 in column 4 and get 8.

So, 6397 + 2399 = 8796.

