Alright, let's solve this problem step by step. We have 664 and 8202 and we're adding them together.

Step 1: We'll start by adding the digits 4 & 2 in column 1 and get 6.

Step 2: We'll start by adding the digits 6 & 0 in column 2 and get 6.

Step 3: We'll start by adding the digits 6 & 2 in column 3 and get 8.

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

So, 664 + 8202 = 8866.

