We've got two numbers: 9726 and 2644. Let's find their sum.

Step 1: We'll start by adding the digits 6 & 4 in column 1 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 2 & 4 in column 2 and get 7.

Step 3: We'll start by adding the digits 7 & 6 in column 3 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 9 & 2 in column 4 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

So, 9726 + 2644 = 12370.

