OK, let's do this. We've got 807402669 and 495584484, and we're subtracting the second number from the first.

Step 1: We'll start by subtracting the digit 4 and the borrow 0 from 9 in column 1 and get 5.
5 is the first digit of our result.

Step 2: We'll start by subtracting the digit 8 and the borrow 0 from 6 in column 2 and get -2.
We add -2 to 10 and get 8 as the next digit of the result.

Step 3: We'll start by subtracting the digit 4 and the borrow 1 from 6 in column 3 and get 1.
1 is the next digit of our result.

Step 4: We'll start by subtracting the digit 4 and the borrow 0 from 2 in column 4 and get -2.
We add -2 to 10 and get 8 as the next digit of the result.

Step 5: We'll start by subtracting the digit 8 and the borrow 1 from 0 in column 5 and get -9.
We add -9 to 10 and get 1 as the next digit of the result.

Step 6: We'll start by subtracting the digit 5 and the borrow 1 from 4 in column 6 and get -2.
We add -2 to 10 and get 8 as the next digit of the result.

Step 7: We'll start by subtracting the digit 5 and the borrow 1 from 7 in column 7 and get 1.
1 is the next digit of our result.

Step 8: We'll start by subtracting the digit 9 and the borrow 0 from 0 in column 8 and get -9.
We add -9 to 10 and get 1 as the next digit of the result.

Step 9: We'll start by subtracting the digit 4 and the borrow 1 from 8 in column 9 and get 3.
3 is the next digit of our result.

So, 807402669 - 495584484 = 311818185.