We've got two numbers: 104 and 720. Let's find their sum.

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

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 1 & 7 in column 3 and get 8.

So, 104 + 720 = 824.

