We look at the division of 563471 by 81 
The aim is to understand the frequency of 81 in 563471.

On to step 1:
The number 81 fits into 5 0 times, leaving a remainder of 5.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Fetch the next digit (6) from the dividend, attach it to 5 and continue: 56 / 81

Going ahead to step 2:
81 goes into 56 0 times with a remainder of 56.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 56, we end up with 56.
Grab the next digit (3) from the dividend, add it to 56, then carry on: 563 / 81

On to step 3:
81 goes into 563 6 times with a remainder of 77.
The next digit of our result is 6. 
Result so far: 6.0
If we take 486 away from 563, we end up with 77.
Fetch the next digit (4) from the dividend, attach it to 77 and continue: 774 / 81

On to step 4:
81 can be fit into 774 9 times, resulting in a remainder of 45.
The number 9 becomes the next digit in our result. 
Result so far: 69.0
If we take 729 away from 774, we end up with 45.
Grab the next digit (7) from the dividend, add it to 45, then carry on: 457 / 81

Advancing to step 5:
81 goes into 457 5 times with a remainder of 52.
Put 5 as the next digit of the answer. 
Result so far: 695.0
Deduct 405 from 457 and we're left with 52.
Fetch the next digit (1) from the dividend, attach it to 52 and continue: 521 / 81

Step 6:
If we divide 521 by 81, we get 6 and a remainder of 35.
Record the quotient 6 as the next digit in the result. 
Result so far: 6956.0
The remainder is 35 after subtracting 486 from 521.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

On to step 7:
81 can be fit into 350 4 times, resulting in a remainder of 26.
Put 4 as the next digit of the answer. 
Result so far: 6956.4
The remainder is 26 after subtracting 324 from 350.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Going ahead to step 8:
81 goes into 260 3 times with a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 6956.43
If we take 243 away from 260, we end up with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Going ahead to step 9:
If we divide 170 by 81, we get 2 and a remainder of 8.
The next digit of our result is 2. 
Result so far: 6956.432
Subtract 162 from 170 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 10:
If we divide 80 by 81, we get 0 and a remainder of 80.
Write down 0 as next digit of the result. 
Result so far: 6956.432
If we take 0 away from 80, we end up with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Let's proceed to step 11:
When dividing 800 by 81, we get 9 with a remainder of 71.
The number 9 becomes the next digit in our result. 
Result so far: 6956.43209
Subtracting 729 from 800 leaves us with 71.
Since there are no more digits in the dividend, we add a zero to the remainder making it 710, and continue the process.

Advancing to step 12:
When dividing 710 by 81, we get 8 with a remainder of 62.
The number 8 becomes the next digit in our result. 
Result so far: 6956.432098
If we subtract 648 from 710, we get 62.
Since there are no more digits in the dividend, we add a zero to the remainder making it 620, and continue the process.

Step 13:
81 goes into 620 7 times with a remainder of 53.
Put 7 as the next digit of the answer. 
Result so far: 6956.4320987
Deduct 567 from 620 and we're left with 53.
Since there are no more digits in the dividend, we add a zero to the remainder making it 530, and continue the process.

Let's proceed to step 14:
The number 81 fits into 530 6 times, leaving a remainder of 44.
The number 6 becomes the next digit in our result. 
Result so far: 6956.43209876
If we subtract 486 from 530, we get 44.
Since there are no more digits in the dividend, we add a zero to the remainder making it 440, and continue the process.

Our division results in 6956.43209876 with a remaining 4.4e-08.