Let's break this down. We're going to add 4972 and 9007 together.

Step 1: We'll start by adding the digits 2 & 7 in column 1 and get 9.

Step 2: We'll start by adding the digits 7 & 0 in column 2 and get 7.

Step 3: We'll start by adding the digits 9 & 0 in column 3 and get 9.

Step 4: We'll start by adding the digits 4 & 9 in column 4 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 4972 + 9007 = 13979.

