We look at the division of 408412 by 81 
The aim is to understand the frequency of 81 in 408412.

Moving on to step 1:
When dividing 4 by 81, we get 0 with a remainder of 4.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Bring next digit (0) of the dividend behind the 4 and repeat the process: 40 / 81

Moving on to step 2:
When dividing 40 by 81, we get 0 with a remainder of 40.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 40, we end up with 40.
Take the next digit (8) from the dividend and append it to 40, then repeat: 408 / 81

Advancing to step 3:
The number 81 fits into 408 5 times, leaving a remainder of 3.
Record the quotient 5 as the next digit in the result. 
Result so far: 5.0
If we subtract 405 from 408, we get 3.
Fetch the next digit (4) from the dividend, attach it to 3 and continue: 34 / 81

Going ahead to step 4:
81 can be fit into 34 0 times, resulting in a remainder of 34.
Record the quotient 0 as the next digit in the result. 
Result so far: 50.0
Subtracting 0 from 34 leaves us with 34.
Append the next digit (1) from the dividend to 34 and continue with: 341 / 81

On to step 5:
When dividing 341 by 81, we get 4 with a remainder of 17.
The next digit of our result is 4. 
Result so far: 504.0
Deduct 324 from 341 and we're left with 17.
Grab the next digit (2) from the dividend, add it to 17, then carry on: 172 / 81

Moving on to step 6:
81 goes into 172 2 times with a remainder of 10.
Use 2 as the next digit of our solution. 
Result so far: 5042.0
If we subtract 162 from 172, 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.

Moving on to step 7:
100 divided by 81 is 1 with a remainder of 19.
Record the quotient 1 as the next digit in the result. 
Result so far: 5042.1
Subtracting 81 from 100 leaves us with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Let's proceed to step 8:
When dividing 190 by 81, we get 2 with a remainder of 28.
Write down 2 as next digit of the result. 
Result so far: 5042.12
The remainder is 28 after subtracting 162 from 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Step 9:
280 divided by 81 is 3 with a remainder of 37.
Put 3 as the next digit of the answer. 
Result so far: 5042.123
Subtracting 243 from 280 leaves us with 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Moving on to step 10:
370 divided by 81 is 4 with a remainder of 46.
Use 4 as the next digit of our solution. 
Result so far: 5042.1234
Deduct 324 from 370 and we're left with 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 460, and continue the process.

Going ahead to step 11:
When dividing 460 by 81, we get 5 with a remainder of 55.
The number 5 becomes the next digit in our result. 
Result so far: 5042.12345
If we subtract 405 from 460, we get 55.
Since there are no more digits in the dividend, we add a zero to the remainder making it 550, and continue the process.

Advancing to step 12:
81 goes into 550 6 times with a remainder of 64.
The number 6 becomes the next digit in our result. 
Result so far: 5042.123456
Subtracting 486 from 550 leaves us with 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Going ahead to step 13:
The number 81 fits into 640 7 times, leaving a remainder of 73.
Record the quotient 7 as the next digit in the result. 
Result so far: 5042.1234567
The remainder is 73 after subtracting 567 from 640.
Since there are no more digits in the dividend, we add a zero to the remainder making it 730, and continue the process.

Let's proceed to step 14:
If we divide 730 by 81, we get 9 and a remainder of 1.
Record the quotient 9 as the next digit in the result. 
Result so far: 5042.12345679
Subtracting 729 from 730 leaves us with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Our division results in 5042.12345679 with a remaining 1e-09.