510175 ÷ 81 
The aim is to understand the frequency of 81 in 510175.

Step 1:
5 divided by 81 is 0 with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 5 leaves us with 5.
Append the next digit (1) from the dividend to 5 and continue with: 51 / 81

Advancing to step 2:
When dividing 51 by 81, we get 0 with a remainder of 51.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 51 leaves us with 51.
Take the next digit (0) from the dividend and append it to 51, then repeat: 510 / 81

On to step 3:
81 can be fit into 510 6 times, resulting in a remainder of 24.
The next digit of our result is 6. 
Result so far: 6.0
If we take 486 away from 510, we end up with 24.
Take the next digit (1) from the dividend and append it to 24, then repeat: 241 / 81

Advancing to step 4:
If we divide 241 by 81, we get 2 and a remainder of 79.
Put 2 as the next digit of the answer. 
Result so far: 62.0
The remainder is 79 after subtracting 162 from 241.
Fetch the next digit (7) from the dividend, attach it to 79 and continue: 797 / 81

On to step 5:
81 goes into 797 9 times with a remainder of 68.
The number 9 becomes the next digit in our result. 
Result so far: 629.0
The remainder is 68 after subtracting 729 from 797.
Grab the next digit (5) from the dividend, add it to 68, then carry on: 685 / 81

Let's proceed to step 6:
81 can be fit into 685 8 times, resulting in a remainder of 37.
The number 8 becomes the next digit in our result. 
Result so far: 6298.0
The remainder is 37 after subtracting 648 from 685.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Step 7:
370 divided by 81 is 4 with a remainder of 46.
Record the quotient 4 as the next digit in the result. 
Result so far: 6298.4
Subtracting 324 from 370 leaves us 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.

Step 8:
If we divide 460 by 81, we get 5 and a remainder of 55.
The number 5 becomes the next digit in our result. 
Result so far: 6298.45
Subtract 405 from 460 to 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 9:
When dividing 550 by 81, we get 6 with a remainder of 64.
Write down 6 as next digit of the result. 
Result so far: 6298.456
Deduct 486 from 550 and we're left 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.

Advancing to step 10:
81 can be fit into 640 7 times, resulting in a remainder of 73.
Use 7 as the next digit of our solution. 
Result so far: 6298.4567
If we take 567 away from 640, we end up with 73.
Since there are no more digits in the dividend, we add a zero to the remainder making it 730, and continue the process.

On to step 11:
81 goes into 730 9 times with a remainder of 1.
Record the quotient 9 as the next digit in the result. 
Result so far: 6298.45679
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.

Advancing to step 12:
10 divided by 81 is 0 with a remainder of 10.
The next digit of our result is 0. 
Result so far: 6298.45679
Subtract 0 from 10 to 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.

Advancing to step 13:
81 goes into 100 1 times with a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 6298.4567901
The remainder is 19 after subtracting 81 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

On to step 14:
The number 81 fits into 190 2 times, leaving a remainder of 28.
The number 2 becomes the next digit in our result. 
Result so far: 6298.45679012
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.

The final result is 6298.45679012 with a remainder of 2.8e-08.