We've got two numbers: 3010 and 644. Let's find their sum.

Step 1: We'll start by adding the digits 0 & 4 in column 1 and get 4.

Step 2: We'll start by adding the digits 1 & 4 in column 2 and get 5.

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 3 & 0 in column 4 and get 3.

So, 3010 + 644 = 3654.

