No problem, let's work through this together. We're starting with 2799 and 3590 and adding them all up.

Step 1: We'll start by adding the digits 9 & 0 in column 1 and get 9.

Step 2: We'll start by adding the digits 9 & 9 in column 2 and get 18.
We'll write down the last digit 8 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 7 & 5 in column 3 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 2 & 3 in column 4 and get 6.

So, 2799 + 3590 = 6389.

