Okay, we are tasked with adding 8615 and 384. Let's begin!

Step 1: We'll start by adding the digits 5 & 4 in column 1 and get 9.

Step 2: We'll start by adding the digits 1 & 8 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 8 & 0 in column 4 and get 8.

So, 8615 + 384 = 8999.

