We've got two numbers: 622 and 3120. Let's find their sum.

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

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

Step 3: We'll start by adding the digits 6 & 1 in column 3 and get 7.

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

So, 622 + 3120 = 3742.

