We have numbers 4661 and 5338. Let's start adding them together.

Step 1: We'll start by adding the digits 1 & 8 in column 1 and get 9.

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 4 & 5 in column 4 and get 9.

So, 4661 + 5338 = 9999.

