We've got two numbers: 4273 and 681. Let's find their sum.

Step 1: We'll start by adding the digits 3 & 1 in column 1 and get 4.

Step 2: We'll start by adding the digits 7 & 8 in column 2 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 2 & 6 in column 3 and get 9.

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

So, 4273 + 681 = 4954.

