Let's divide 629190 by 21
The aim is to understand the frequency of 21 in 629190.

Let's proceed to step 1:
When dividing 6 by 21, we get 0 with a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Bring next digit (2) of the dividend behind the 6 and repeat the process: 62 / 21

Advancing to step 2:
21 goes into 62 2 times with a remainder of 20.
Use 2 as the next digit of our solution. 
Result so far: 2.0
Subtracting 42 from 62 leaves us with 20.
Append the next digit (9) from the dividend to 20 and continue with: 209 / 21

On to step 3:
When dividing 209 by 21, we get 9 with a remainder of 20.
The next digit of our result is 9. 
Result so far: 29.0
If we take 189 away from 209, we end up with 20.
Take the next digit (1) from the dividend and append it to 20, then repeat: 201 / 21

Let's proceed to step 4:
21 can be fit into 201 9 times, resulting in a remainder of 12.
The next digit of our result is 9. 
Result so far: 299.0
If we subtract 189 from 201, we get 12.
Take the next digit (9) from the dividend and append it to 12, then repeat: 129 / 21

Let's proceed to step 5:
21 goes into 129 6 times with a remainder of 3.
Put 6 as the next digit of the answer. 
Result so far: 2996.0
Deduct 126 from 129 and we're left with 3.
Bring next digit (0) of the dividend behind the 3 and repeat the process: 30 / 21

Let's proceed to step 6:
When dividing 30 by 21, we get 1 with a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 29961.0
Deduct 21 from 30 and we're left 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 7:
If we divide 90 by 21, we get 4 and a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 29961.4
Subtract 84 from 90 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 8:
21 goes into 60 2 times with a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 29961.42
Subtract 42 from 60 to 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.

Advancing to step 9:
If we divide 180 by 21, we get 8 and a remainder of 12.
The next digit of our result is 8. 
Result so far: 29961.428
If we subtract 168 from 180, we 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.

Advancing to step 10:
When dividing 120 by 21, we get 5 with a remainder of 15.
The next digit of our result is 5. 
Result so far: 29961.4285
The remainder is 15 after subtracting 105 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 11:
The number 21 fits into 150 7 times, leaving a remainder of 3.
Put 7 as the next digit of the answer. 
Result so far: 29961.42857
The remainder is 3 after subtracting 147 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Step 12:
30 divided by 21 is 1 with a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 29961.428571
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.

Let's proceed to step 13:
The number 21 fits into 90 4 times, leaving a remainder of 6.
Put 4 as the next digit of the answer. 
Result so far: 29961.4285714
The remainder is 6 after subtracting 84 from 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 14:
If we divide 60 by 21, we get 2 and a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 29961.42857142
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.

After the division, we end up with 29961.42857142 and a remainder of 1.8e-08.