Let's divide 903307 by 81
The aim is to understand the frequency of 81 in 903307.

On to step 1:
If we divide 9 by 81, we get 0 and a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 9, we get 9.
Grab the next digit (0) from the dividend, add it to 9, then carry on: 90 / 81

Going ahead to step 2:
If we divide 90 by 81, we get 1 and a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtract 81 from 90 to get 9.
Take the next digit (3) from the dividend and append it to 9, then repeat: 93 / 81

Going ahead to step 3:
81 goes into 93 1 times with a remainder of 12.
The number 1 becomes the next digit in our result. 
Result so far: 11.0
If we subtract 81 from 93, we get 12.
Fetch the next digit (3) from the dividend, attach it to 12 and continue: 123 / 81

Going ahead to step 4:
81 goes into 123 1 times with a remainder of 42.
Record the quotient 1 as the next digit in the result. 
Result so far: 111.0
If we subtract 81 from 123, we get 42.
Bring next digit (0) of the dividend behind the 42 and repeat the process: 420 / 81

Step 5:
When dividing 420 by 81, we get 5 with a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 1115.0
The remainder is 15 after subtracting 405 from 420.
Fetch the next digit (7) from the dividend, attach it to 15 and continue: 157 / 81

On to step 6:
81 goes into 157 1 times with a remainder of 76.
Record the quotient 1 as the next digit in the result. 
Result so far: 11151.0
If we subtract 81 from 157, we get 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Advancing to step 7:
The number 81 fits into 760 9 times, leaving a remainder of 31.
Record the quotient 9 as the next digit in the result. 
Result so far: 11151.9
If we subtract 729 from 760, we get 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

On to step 8:
310 divided by 81 is 3 with a remainder of 67.
The number 3 becomes the next digit in our result. 
Result so far: 11151.93
If we take 243 away from 310, we end up with 67.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

Moving on to step 9:
The number 81 fits into 670 8 times, leaving a remainder of 22.
Write down 8 as next digit of the result. 
Result so far: 11151.938
Deduct 648 from 670 and we're left with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Step 10:
81 can be fit into 220 2 times, resulting in a remainder of 58.
Record the quotient 2 as the next digit in the result. 
Result so far: 11151.9382
Deduct 162 from 220 and we're left with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

On to step 11:
580 divided by 81 is 7 with a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 11151.93827
If we take 567 away from 580, we end up with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

On to step 12:
81 can be fit into 130 1 times, resulting in a remainder of 49.
Write down 1 as next digit of the result. 
Result so far: 11151.938271
Deduct 81 from 130 and we're left with 49.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

Going ahead to step 13:
When dividing 490 by 81, we get 6 with a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 11151.9382716
Subtracting 486 from 490 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 14:
When dividing 40 by 81, we get 0 with a remainder of 40.
Record the quotient 0 as the next digit in the result. 
Result so far: 11151.9382716
Deduct 0 from 40 and we're left with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

The final outcome is 11151.9382716, with a leftover of 4e-08.