We're dividing 174957 by 21 
The aim is to understand the frequency of 21 in 174957.

Going ahead to step 1:
When dividing 1 by 21, we get 0 with a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Fetch the next digit (7) from the dividend, attach it to 1 and continue: 17 / 21

Advancing to step 2:
21 goes into 17 0 times with a remainder of 17.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 17 after subtracting 0 from 17.
Bring next digit (4) of the dividend behind the 17 and repeat the process: 174 / 21

On to step 3:
If we divide 174 by 21, we get 8 and a remainder of 6.
Use 8 as the next digit of our solution. 
Result so far: 8.0
If we take 168 away from 174, we end up with 6.
Include the next digit (9) from the dividend after 6, then repeat: 69 / 21

Moving on to step 4:
The number 21 fits into 69 3 times, leaving a remainder of 6.
Write down 3 as next digit of the result. 
Result so far: 83.0
The remainder is 6 after subtracting 63 from 69.
Fetch the next digit (5) from the dividend, attach it to 6 and continue: 65 / 21

Advancing to step 5:
The number 21 fits into 65 3 times, leaving a remainder of 2.
Write down 3 as next digit of the result. 
Result so far: 833.0
Subtracting 63 from 65 leaves us with 2.
Grab the next digit (7) from the dividend, add it to 2, then carry on: 27 / 21

Moving on to step 6:
When dividing 27 by 21, we get 1 with a remainder of 6.
The number 1 becomes the next digit in our result. 
Result so far: 8331.0
Subtract 21 from 27 to get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Moving on to step 7:
21 goes into 60 2 times with a remainder of 18.
The next digit of our result is 2. 
Result so far: 8331.2
Subtracting 42 from 60 leaves us with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Let's proceed to step 8:
21 goes into 180 8 times with a remainder of 12.
The next digit of our result is 8. 
Result so far: 8331.28
Subtracting 168 from 180 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 9:
21 goes into 120 5 times with a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 8331.285
If we subtract 105 from 120, we get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Advancing to step 10:
150 divided by 21 is 7 with a remainder of 3.
Put 7 as the next digit of the answer. 
Result so far: 8331.2857
Subtract 147 from 150 to get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 11:
If we divide 30 by 21, we get 1 and a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 8331.28571
If we take 21 away from 30, we end up with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 12:
21 can be fit into 90 4 times, resulting in a remainder of 6.
Write down 4 as next digit of the result. 
Result so far: 8331.285714
Deduct 84 from 90 and we're left with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Advancing to step 13:
21 can be fit into 60 2 times, resulting in a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 8331.2857142
If we subtract 42 from 60, we get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Let's proceed to step 14:
When dividing 180 by 21, we get 8 with a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 8331.28571428
Subtract 168 from 180 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

In conclusion, the division gives 8331.28571428 with a balance of 1.2e-08.