Okay, we are tasked with adding 2040 and 5659. Let's begin!

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

Step 2: We'll start by adding the digits 4 & 5 in column 2 and get 9.

Step 3: We'll start by adding the digits 0 & 6 in column 3 and get 6.

Step 4: We'll start by adding the digits 2 & 5 in column 4 and get 7.

So, 2040 + 5659 = 7699.

