Let's break this down. We're going to add 660 and 5337 together.

Step 1: We'll start by adding the digits 0 & 7 in column 1 and get 7.

Step 2: We'll start by adding the digits 6 & 3 in column 2 and get 9.

Step 3: We'll start by adding the digits 6 & 3 in column 3 and get 9.

Step 4: We'll start by adding the digits 0 & 5 in column 4 and get 5.

So, 660 + 5337 = 5997.

