Okay, we are tasked with adding 4517 and 2100. Let's begin!

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

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

Step 3: We'll start by adding the digits 5 & 1 in column 3 and get 6.

Step 4: We'll start by adding the digits 4 & 2 in column 4 and get 6.

So, 4517 + 2100 = 6617.

