Okay, we are tasked with adding 3005 and 5640. Let's begin!

Step 1: We'll start by adding the digits 5 & 0 in column 1 and get 5.

Step 2: We'll start by adding the digits 0 & 4 in column 2 and get 4.

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 3 & 5 in column 4 and get 8.

So, 3005 + 5640 = 8645.

