We divide 515609 by 81
The aim is to understand the frequency of 81 in 515609.

Going ahead to step 1:
The number 81 fits into 5 0 times, leaving a remainder of 5.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Include the next digit (1) from the dividend after 5, then repeat: 51 / 81

On to step 2:
If we divide 51 by 81, we get 0 and a remainder of 51.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 51, we get 51.
Fetch the next digit (5) from the dividend, attach it to 51 and continue: 515 / 81

Moving on to step 3:
515 divided by 81 is 6 with a remainder of 29.
Write down 6 as next digit of the result. 
Result so far: 6.0
Subtracting 486 from 515 leaves us with 29.
Bring next digit (6) of the dividend behind the 29 and repeat the process: 296 / 81

Going ahead to step 4:
81 can be fit into 296 3 times, resulting in a remainder of 53.
The next digit of our result is 3. 
Result so far: 63.0
Subtract 243 from 296 to get 53.
Grab the next digit (0) from the dividend, add it to 53, then carry on: 530 / 81

Let's proceed to step 5:
If we divide 530 by 81, we get 6 and a remainder of 44.
Put 6 as the next digit of the answer. 
Result so far: 636.0
If we subtract 486 from 530, we get 44.
Bring next digit (9) of the dividend behind the 44 and repeat the process: 449 / 81

Going ahead to step 6:
449 divided by 81 is 5 with a remainder of 44.
Put 5 as the next digit of the answer. 
Result so far: 6365.0
If we subtract 405 from 449, we get 44.
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:
If we divide 440 by 81, we get 5 and a remainder of 35.
The number 5 becomes the next digit in our result. 
Result so far: 6365.5
Subtracting 405 from 440 leaves us 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.

Moving on to step 8:
The number 81 fits into 350 4 times, leaving a remainder of 26.
The next digit of our result is 4. 
Result so far: 6365.54
If we subtract 324 from 350, we 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.

On to step 9:
When dividing 260 by 81, we get 3 with a remainder of 17.
Put 3 as the next digit of the answer. 
Result so far: 6365.543
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:
The number 81 fits into 170 2 times, leaving a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 6365.5432
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.

Step 11:
80 divided by 81 is 0 with a remainder of 80.
The next digit of our result is 0. 
Result so far: 6365.5432
If we subtract 0 from 80, we get 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 12:
The number 81 fits into 800 9 times, leaving a remainder of 71.
Write down 9 as next digit of the result. 
Result so far: 6365.543209
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.

Moving on to step 13:
If we divide 710 by 81, we get 8 and a remainder of 62.
The next digit of our result is 8. 
Result so far: 6365.5432098
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 14:
The number 81 fits into 620 7 times, leaving a remainder of 53.
The number 7 becomes the next digit in our result. 
Result so far: 6365.54320987
The remainder is 53 after subtracting 567 from 620.
Since there are no more digits in the dividend, we add a zero to the remainder making it 530, and continue the process.

The final result is 6365.54320987 with a remainder of 5.3e-08.