We divide 199551 by 21
The aim is to understand the frequency of 21 in 199551.

Step 1:
When dividing 1 by 21, we get 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Take the next digit (9) from the dividend and append it to 1, then repeat: 19 / 21

Going ahead to step 2:
When dividing 19 by 21, we get 0 with a remainder of 19.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 19 after subtracting 0 from 19.
Fetch the next digit (9) from the dividend, attach it to 19 and continue: 199 / 21

Step 3:
199 divided by 21 is 9 with a remainder of 10.
Put 9 as the next digit of the answer. 
Result so far: 9.0
If we take 189 away from 199, we end up with 10.
Append the next digit (5) from the dividend to 10 and continue with: 105 / 21

Step 4:
21 can be fit into 105 5 times, resulting in a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 95.0
Subtract 105 from 105 to get 0.
Append the next digit (5) from the dividend to 0 and continue with: 5 / 21

Step 5:
5 divided by 21 is 0 with a remainder of 5.
The number 0 becomes the next digit in our result. 
Result so far: 950.0
Subtract 0 from 5 to get 5.
Append the next digit (1) from the dividend to 5 and continue with: 51 / 21

Moving on to step 6:
51 divided by 21 is 2 with a remainder of 9.
Record the quotient 2 as the next digit in the result. 
Result so far: 9502.0
Subtracting 42 from 51 leaves us 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.

Let's proceed to step 7:
21 goes into 90 4 times with a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 9502.4
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 8:
The number 21 fits into 60 2 times, leaving a remainder of 18.
Use 2 as the next digit of our solution. 
Result so far: 9502.42
Deduct 42 from 60 and we're left 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.

Moving on to step 9:
180 divided by 21 is 8 with a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 9502.428
If we take 168 away from 180, we end up 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 10:
21 can be fit into 120 5 times, resulting in a remainder of 15.
Use 5 as the next digit of our solution. 
Result so far: 9502.4285
Subtract 105 from 120 to 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.

Step 11:
The number 21 fits into 150 7 times, leaving a remainder of 3.
The number 7 becomes the next digit in our result. 
Result so far: 9502.42857
If we subtract 147 from 150, we 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.

Moving on to step 12:
When dividing 30 by 21, we get 1 with a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 9502.428571
Subtracting 21 from 30 leaves us 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.

Moving on to step 13:
90 divided by 21 is 4 with a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 9502.4285714
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.

Going ahead to step 14:
When dividing 60 by 21, we get 2 with a remainder of 18.
The next digit of our result is 2. 
Result so far: 9502.42857142
If we take 42 away from 60, we end up 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.

The quotient of the division is 9502.42857142, and the remainder is 1.8e-08.