Not to worry, we've got 4017 and 1620. Let's get to adding them!

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 & 2 in column 2 and get 3.

Step 3: We'll start by adding the digits 0 & 6 in column 3 and get 6.

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

So, 4017 + 1620 = 5637.

