We divide 98405692 by 21
The aim is to understand the frequency of 21 in 98405692.

Going ahead to step 1:
9 divided by 21 is 0 with a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 9 after subtracting 0 from 9.
Bring next digit (8) of the dividend behind the 9 and repeat the process: 98 / 21

Let's proceed to step 2:
When dividing 98 by 21, we get 4 with a remainder of 14.
Use 4 as the next digit of our solution. 
Result so far: 4.0
Subtract 84 from 98 to get 14.
Bring next digit (4) of the dividend behind the 14 and repeat the process: 144 / 21

Let's proceed to step 3:
144 divided by 21 is 6 with a remainder of 18.
The number 6 becomes the next digit in our result. 
Result so far: 46.0
Subtracting 126 from 144 leaves us with 18.
Append the next digit (0) from the dividend to 18 and continue with: 180 / 21

Going ahead to step 4:
The number 21 fits into 180 8 times, leaving a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 468.0
The remainder is 12 after subtracting 168 from 180.
Append the next digit (5) from the dividend to 12 and continue with: 125 / 21

Moving on to step 5:
When dividing 125 by 21, we get 5 with a remainder of 20.
The next digit of our result is 5. 
Result so far: 4685.0
Subtract 105 from 125 to get 20.
Fetch the next digit (6) from the dividend, attach it to 20 and continue: 206 / 21

Let's proceed to step 6:
If we divide 206 by 21, we get 9 and a remainder of 17.
Put 9 as the next digit of the answer. 
Result so far: 46859.0
If we take 189 away from 206, we end up with 17.
Include the next digit (9) from the dividend after 17, then repeat: 179 / 21

On to step 7:
179 divided by 21 is 8 with a remainder of 11.
The number 8 becomes the next digit in our result. 
Result so far: 468598.0
Deduct 168 from 179 and we're left with 11.
Include the next digit (2) from the dividend after 11, then repeat: 112 / 21

Going ahead to step 8:
21 can be fit into 112 5 times, resulting in a remainder of 7.
The next digit of our result is 5. 
Result so far: 4685985.0
Subtract 105 from 112 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Moving on to step 9:
If we divide 70 by 21, we get 3 and a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 4685985.3
If we subtract 63 from 70, we get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 10:
21 goes into 70 3 times with a remainder of 7.
Write down 3 as next digit of the result. 
Result so far: 4685985.33
Subtracting 63 from 70 leaves us with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

The final result is 4685985.33 with a remainder of 0.007.