646089 ÷ 80 
Let's see how many times 80 fits into 646089.

On to step 1:
The number 80 fits into 6 0 times, leaving a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Bring next digit (4) of the dividend behind the 6 and repeat the process: 64 / 80

Step 2:
64 divided by 80 is 0 with a remainder of 64.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 64, we get 64.
Append the next digit (6) from the dividend to 64 and continue with: 646 / 80

On to step 3:
If we divide 646 by 80, we get 8 and a remainder of 6.
The number 8 becomes the next digit in our result. 
Result so far: 8.0
Deduct 640 from 646 and we're left with 6.
Bring next digit (0) of the dividend behind the 6 and repeat the process: 60 / 80

Step 4:
80 goes into 60 0 times with a remainder of 60.
The next digit of our result is 0. 
Result so far: 80.0
Deduct 0 from 60 and we're left with 60.
Append the next digit (8) from the dividend to 60 and continue with: 608 / 80

Going ahead to step 5:
608 divided by 80 is 7 with a remainder of 48.
The next digit of our result is 7. 
Result so far: 807.0
Deduct 560 from 608 and we're left with 48.
Include the next digit (9) from the dividend after 48, then repeat: 489 / 80

Step 6:
80 can be fit into 489 6 times, resulting in a remainder of 9.
Record the quotient 6 as the next digit in the result. 
Result so far: 8076.0
If we take 480 away from 489, we end up with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 7:
If we divide 90 by 80, we get 1 and a remainder of 10.
Write down 1 as next digit of the result. 
Result so far: 8076.1
If we subtract 80 from 90, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Step 8:
80 goes into 100 1 times with a remainder of 20.
Write down 1 as next digit of the result. 
Result so far: 8076.11
If we take 80 away from 100, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final result is 8076.11 with a remainder of 0.02.