Let's divide 9961753 by 21
The aim is to understand the frequency of 21 in 9961753.

Advancing to step 1:
If we divide 9 by 21, we get 0 and a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 9 after subtracting 0 from 9.
Take the next digit (9) from the dividend and append it to 9, then repeat: 99 / 21

Advancing to step 2:
If we divide 99 by 21, we get 4 and a remainder of 15.
The next digit of our result is 4. 
Result so far: 4.0
Subtract 84 from 99 to get 15.
Bring next digit (6) of the dividend behind the 15 and repeat the process: 156 / 21

Moving on to step 3:
When dividing 156 by 21, we get 7 with a remainder of 9.
Put 7 as the next digit of the answer. 
Result so far: 47.0
If we take 147 away from 156, we end up with 9.
Bring next digit (1) of the dividend behind the 9 and repeat the process: 91 / 21

Going ahead to step 4:
The number 21 fits into 91 4 times, leaving a remainder of 7.
The next digit of our result is 4. 
Result so far: 474.0
Subtracting 84 from 91 leaves us with 7.
Grab the next digit (7) from the dividend, add it to 7, then carry on: 77 / 21

Going ahead to step 5:
77 divided by 21 is 3 with a remainder of 14.
Use 3 as the next digit of our solution. 
Result so far: 4743.0
Subtracting 63 from 77 leaves us with 14.
Take the next digit (5) from the dividend and append it to 14, then repeat: 145 / 21

Advancing to step 6:
When dividing 145 by 21, we get 6 with a remainder of 19.
Write down 6 as next digit of the result. 
Result so far: 47436.0
Subtracting 126 from 145 leaves us with 19.
Fetch the next digit (3) from the dividend, attach it to 19 and continue: 193 / 21

Step 7:
When dividing 193 by 21, we get 9 with a remainder of 4.
The next digit of our result is 9. 
Result so far: 474369.0
Subtracting 189 from 193 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 8:
When dividing 40 by 21, we get 1 with a remainder of 19.
Write down 1 as next digit of the result. 
Result so far: 474369.1
The remainder is 19 after subtracting 21 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 9:
If we divide 190 by 21, we get 9 and a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 474369.19
Deduct 189 from 190 and we're left 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.

Moving on to step 10:
When dividing 10 by 21, we get 0 with a remainder of 10.
The next digit of our result is 0. 
Result so far: 474369.19
If we take 0 away from 10, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 11:
If we divide 100 by 21, we get 4 and a remainder of 16.
Write down 4 as next digit of the result. 
Result so far: 474369.1904
Deduct 84 from 100 and we're left with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Moving on to step 12:
The number 21 fits into 160 7 times, leaving a remainder of 13.
Put 7 as the next digit of the answer. 
Result so far: 474369.19047
Subtracting 147 from 160 leaves us with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Going ahead to step 13:
21 goes into 130 6 times with a remainder of 4.
The next digit of our result is 6. 
Result so far: 474369.190476
If we take 126 away from 130, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 14:
The number 21 fits into 40 1 times, leaving a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 474369.1904761
If we take 21 away from 40, we end up with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Let's proceed to step 15:
If we divide 190 by 21, we get 9 and a remainder of 1.
Write down 9 as next digit of the result. 
Result so far: 474369.19047619
Subtract 189 from 190 to get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Our division results in 474369.19047619 with a remaining 1e-09.