We look at the division of 749537 by 81 
The aim is to understand the frequency of 81 in 749537.

Advancing to step 1:
When dividing 7 by 81, we get 0 with a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 7 leaves us with 7.
Take the next digit (4) from the dividend and append it to 7, then repeat: 74 / 81

Moving on to step 2:
When dividing 74 by 81, we get 0 with a remainder of 74.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 74 after subtracting 0 from 74.
Append the next digit (9) from the dividend to 74 and continue with: 749 / 81

Moving on to step 3:
81 can be fit into 749 9 times, resulting in a remainder of 20.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
Subtract 729 from 749 to get 20.
Append the next digit (5) from the dividend to 20 and continue with: 205 / 81

Step 4:
81 goes into 205 2 times with a remainder of 43.
Write down 2 as next digit of the result. 
Result so far: 92.0
If we take 162 away from 205, we end up with 43.
Grab the next digit (3) from the dividend, add it to 43, then carry on: 433 / 81

Going ahead to step 5:
If we divide 433 by 81, we get 5 and a remainder of 28.
The number 5 becomes the next digit in our result. 
Result so far: 925.0
If we subtract 405 from 433, we get 28.
Append the next digit (7) from the dividend to 28 and continue with: 287 / 81

Step 6:
81 goes into 287 3 times with a remainder of 44.
Write down 3 as next digit of the result. 
Result so far: 9253.0
The remainder is 44 after subtracting 243 from 287.
Since there are no more digits in the dividend, we add a zero to the remainder making it 440, and continue the process.

Moving on to step 7:
The number 81 fits into 440 5 times, leaving a remainder of 35.
The next digit of our result is 5. 
Result so far: 9253.5
If we take 405 away from 440, we end up with 35.
Since there are no more digits in the dividend, we add a zero to the remainder making it 350, and continue the process.

Let's proceed to step 8:
81 goes into 350 4 times with a remainder of 26.
Put 4 as the next digit of the answer. 
Result so far: 9253.54
Subtract 324 from 350 to get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Advancing to step 9:
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: 9253.543
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.

On to step 10:
When dividing 170 by 81, we get 2 with a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 9253.5432
If we take 162 away from 170, we end up with 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 11:
80 divided by 81 is 0 with a remainder of 80.
The next digit of our result is 0. 
Result so far: 9253.5432
The remainder is 80 after subtracting 0 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Going ahead to step 12:
If we divide 800 by 81, we get 9 and a remainder of 71.
Write down 9 as next digit of the result. 
Result so far: 9253.543209
If we take 729 away from 800, we end up 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.

Moving on to step 13:
710 divided by 81 is 8 with a remainder of 62.
Use 8 as the next digit of our solution. 
Result so far: 9253.5432098
Deduct 648 from 710 and we're left with 62.
Since there are no more digits in the dividend, we add a zero to the remainder making it 620, and continue the process.

On to step 14:
620 divided by 81 is 7 with a remainder of 53.
Record the quotient 7 as the next digit in the result. 
Result so far: 9253.54320987
If we take 567 away from 620, we end up 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.

After the division, we end up with 9253.54320987 and a remainder of 5.3e-08.