Alright, let's solve this problem step by step. We have 6421 and 2060 and we're adding them together.

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

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

Step 3: We'll start by adding the digits 4 & 0 in column 3 and get 4.

Step 4: We'll start by adding the digits 6 & 2 in column 4 and get 8.

So, 6421 + 2060 = 8481.

