662571 ÷ 81 
The aim is to understand the frequency of 81 in 662571.

Going ahead to step 1:
81 can be fit into 6 0 times, resulting in a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Append the next digit (6) from the dividend to 6 and continue with: 66 / 81

Advancing to step 2:
81 can be fit into 66 0 times, resulting in a remainder of 66.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 66 after subtracting 0 from 66.
Take the next digit (2) from the dividend and append it to 66, then repeat: 662 / 81

Advancing to step 3:
If we divide 662 by 81, we get 8 and a remainder of 14.
The next digit of our result is 8. 
Result so far: 8.0
Deduct 648 from 662 and we're left with 14.
Bring next digit (5) of the dividend behind the 14 and repeat the process: 145 / 81

Step 4:
145 divided by 81 is 1 with a remainder of 64.
Record the quotient 1 as the next digit in the result. 
Result so far: 81.0
Subtracting 81 from 145 leaves us with 64.
Take the next digit (7) from the dividend and append it to 64, then repeat: 647 / 81

Moving on to step 5:
If we divide 647 by 81, we get 7 and a remainder of 80.
Use 7 as the next digit of our solution. 
Result so far: 817.0
If we subtract 567 from 647, we get 80.
Grab the next digit (1) from the dividend, add it to 80, then carry on: 801 / 81

Advancing to step 6:
The number 81 fits into 801 9 times, leaving a remainder of 72.
Record the quotient 9 as the next digit in the result. 
Result so far: 8179.0
If we take 729 away from 801, we end up with 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Advancing to step 7:
When dividing 720 by 81, we get 8 with a remainder of 72.
Use 8 as the next digit of our solution. 
Result so far: 8179.8
Subtracting 648 from 720 leaves us with 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Moving on to step 8:
The number 81 fits into 720 8 times, leaving a remainder of 72.
The number 8 becomes the next digit in our result. 
Result so far: 8179.88
Subtracting 648 from 720 leaves us with 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

After the division, we end up with 8179.88 and a remainder of 0.072.