Alright, let's solve this problem step by step. We have 401 and 4221 and we're adding them together.

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

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

Step 3: We'll start by adding the digits 4 & 2 in column 3 and get 6.

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

So, 401 + 4221 = 4622.

