We've got two numbers: 4720 and 4278. Let's find their sum.

Step 1: We'll start by adding the digits 0 & 8 in column 1 and get 8.

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

Step 3: We'll start by adding the digits 7 & 2 in column 3 and get 9.

Step 4: We'll start by adding the digits 4 & 4 in column 4 and get 8.

So, 4720 + 4278 = 8998.

