Let's divide 665149 by 81
The aim is to understand the frequency of 81 in 665149.

On to step 1:
The number 81 fits into 6 0 times, leaving a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Include the next digit (6) from the dividend after 6, then repeat: 66 / 81

On to step 2:
If we divide 66 by 81, we get 0 and a remainder of 66.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 66, we end up with 66.
Grab the next digit (5) from the dividend, add it to 66, then carry on: 665 / 81

Advancing to step 3:
81 can be fit into 665 8 times, resulting in a remainder of 17.
Use 8 as the next digit of our solution. 
Result so far: 8.0
Subtracting 648 from 665 leaves us with 17.
Take the next digit (1) from the dividend and append it to 17, then repeat: 171 / 81

On to step 4:
If we divide 171 by 81, we get 2 and a remainder of 9.
The number 2 becomes the next digit in our result. 
Result so far: 82.0
If we take 162 away from 171, we end up with 9.
Bring next digit (4) of the dividend behind the 9 and repeat the process: 94 / 81

Moving on to step 5:
81 goes into 94 1 times with a remainder of 13.
The next digit of our result is 1. 
Result so far: 821.0
Deduct 81 from 94 and we're left with 13.
Append the next digit (9) from the dividend to 13 and continue with: 139 / 81

Step 6:
81 can be fit into 139 1 times, resulting in a remainder of 58.
The next digit of our result is 1. 
Result so far: 8211.0
If we take 81 away from 139, we end up 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.

Moving on to step 7:
81 can be fit into 580 7 times, resulting in a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 8211.7
Subtracting 567 from 580 leaves us 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.

Step 8:
When dividing 130 by 81, we get 1 with a remainder of 49.
Record the quotient 1 as the next digit in the result. 
Result so far: 8211.71
If we subtract 81 from 130, we get 49.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

Moving on to step 9:
If we divide 490 by 81, we get 6 and a remainder of 4.
Write down 6 as next digit of the result. 
Result so far: 8211.716
If we take 486 away from 490, we end up 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.

On to step 10:
81 goes into 40 0 times with a remainder of 40.
Use 0 as the next digit of our solution. 
Result so far: 8211.716
If we subtract 0 from 40, we get 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Moving on to step 11:
81 goes into 400 4 times with a remainder of 76.
Record the quotient 4 as the next digit in the result. 
Result so far: 8211.71604
The remainder is 76 after subtracting 324 from 400.
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 12:
The number 81 fits into 760 9 times, leaving a remainder of 31.
The number 9 becomes the next digit in our result. 
Result so far: 8211.716049
Deduct 729 from 760 and we're left with 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 13:
If we divide 310 by 81, we get 3 and a remainder of 67.
Put 3 as the next digit of the answer. 
Result so far: 8211.7160493
Subtracting 243 from 310 leaves us 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.

On to step 14:
When dividing 670 by 81, we get 8 with a remainder of 22.
The next digit of our result is 8. 
Result so far: 8211.71604938
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.

The final result is 8211.71604938 with a remainder of 2.2e-08.