We look at the division of 462285 by 21 
The aim is to understand the frequency of 21 in 462285.

Advancing to step 1:
21 can be fit into 4 0 times, resulting in a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Include the next digit (6) from the dividend after 4, then repeat: 46 / 21

Step 2:
The number 21 fits into 46 2 times, leaving a remainder of 4.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Subtract 42 from 46 to get 4.
Fetch the next digit (2) from the dividend, attach it to 4 and continue: 42 / 21

Moving on to step 3:
21 can be fit into 42 2 times, resulting in a remainder of 0.
Write down 2 as next digit of the result. 
Result so far: 22.0
Subtract 42 from 42 to get 0.
Take the next digit (2) from the dividend and append it to 0, then repeat: 2 / 21

On to step 4:
The number 21 fits into 2 0 times, leaving a remainder of 2.
The next digit of our result is 0. 
Result so far: 220.0
Deduct 0 from 2 and we're left with 2.
Fetch the next digit (8) from the dividend, attach it to 2 and continue: 28 / 21

Advancing to step 5:
28 divided by 21 is 1 with a remainder of 7.
Use 1 as the next digit of our solution. 
Result so far: 2201.0
If we take 21 away from 28, we end up with 7.
Append the next digit (5) from the dividend to 7 and continue with: 75 / 21

Let's proceed to step 6:
If we divide 75 by 21, we get 3 and a remainder of 12.
Write down 3 as next digit of the result. 
Result so far: 22013.0
Deduct 63 from 75 and we're left 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.

Moving on to step 7:
120 divided by 21 is 5 with a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 22013.5
Subtracting 105 from 120 leaves us with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 8:
If we divide 150 by 21, we get 7 and a remainder of 3.
Record the quotient 7 as the next digit in the result. 
Result so far: 22013.57
Deduct 147 from 150 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Advancing to step 9:
21 goes into 30 1 times with a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 22013.571
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 10:
90 divided by 21 is 4 with a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 22013.5714
If we take 84 away from 90, we end up 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.

Let's proceed to step 11:
When dividing 60 by 21, we get 2 with a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 22013.57142
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.

Moving on to step 12:
21 can be fit into 180 8 times, resulting in a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 22013.571428
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.

Step 13:
When dividing 120 by 21, we get 5 with a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 22013.5714285
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.

On to step 14:
The number 21 fits into 150 7 times, leaving a remainder of 3.
The next digit of our result is 7. 
Result so far: 22013.57142857
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.

The final result is 22013.57142857 with a remainder of 3e-09.