We look at the division of 843632 by 81 
The aim is to understand the frequency of 81 in 843632.

Let's proceed to step 1:
If we divide 8 by 81, we get 0 and a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Append the next digit (4) from the dividend to 8 and continue with: 84 / 81

Moving on to step 2:
81 goes into 84 1 times with a remainder of 3.
The next digit of our result is 1. 
Result so far: 1.0
If we subtract 81 from 84, we get 3.
Append the next digit (3) from the dividend to 3 and continue with: 33 / 81

Going ahead to step 3:
81 can be fit into 33 0 times, resulting in a remainder of 33.
Record the quotient 0 as the next digit in the result. 
Result so far: 10.0
Deduct 0 from 33 and we're left with 33.
Bring next digit (6) of the dividend behind the 33 and repeat the process: 336 / 81

Going ahead to step 4:
81 can be fit into 336 4 times, resulting in a remainder of 12.
The number 4 becomes the next digit in our result. 
Result so far: 104.0
Subtracting 324 from 336 leaves us with 12.
Take the next digit (3) from the dividend and append it to 12, then repeat: 123 / 81

Advancing to step 5:
81 goes into 123 1 times with a remainder of 42.
The next digit of our result is 1. 
Result so far: 1041.0
If we subtract 81 from 123, we get 42.
Take the next digit (2) from the dividend and append it to 42, then repeat: 422 / 81

Let's proceed to step 6:
422 divided by 81 is 5 with a remainder of 17.
The next digit of our result is 5. 
Result so far: 10415.0
If we take 405 away from 422, 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.

On to step 7:
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: 10415.2
If we subtract 162 from 170, we 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.

Going ahead to step 8:
81 can be fit into 80 0 times, resulting in a remainder of 80.
The number 0 becomes the next digit in our result. 
Result so far: 10415.2
Subtracting 0 from 80 leaves us 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 9:
81 can be fit into 800 9 times, resulting in a remainder of 71.
Put 9 as the next digit of the answer. 
Result so far: 10415.209
Subtract 729 from 800 to get 71.
Since there are no more digits in the dividend, we add a zero to the remainder making it 710, and continue the process.

Step 10:
The number 81 fits into 710 8 times, leaving a remainder of 62.
Use 8 as the next digit of our solution. 
Result so far: 10415.2098
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.

Moving on to step 11:
The number 81 fits into 620 7 times, leaving a remainder of 53.
Use 7 as the next digit of our solution. 
Result so far: 10415.20987
If we subtract 567 from 620, we get 53.
Since there are no more digits in the dividend, we add a zero to the remainder making it 530, and continue the process.

Advancing to step 12:
81 goes into 530 6 times with a remainder of 44.
Use 6 as the next digit of our solution. 
Result so far: 10415.209876
If we take 486 away from 530, we end up with 44.
Since there are no more digits in the dividend, we add a zero to the remainder making it 440, and continue the process.

Step 13:
81 goes into 440 5 times with a remainder of 35.
The number 5 becomes the next digit in our result. 
Result so far: 10415.2098765
The remainder is 35 after subtracting 405 from 440.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Moving on to step 14:
81 goes into 350 4 times with a remainder of 26.
Record the quotient 4 as the next digit in the result. 
Result so far: 10415.20987654
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.

The quotient of the division is 10415.20987654, and the remainder is 2.6e-08.