134823 ÷ 21 
The aim is to understand the frequency of 21 in 134823.

Moving on to step 1:
When dividing 1 by 21, we get 0 with a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Grab the next digit (3) from the dividend, add it to 1, then carry on: 13 / 21

Let's proceed to step 2:
The number 21 fits into 13 0 times, leaving a remainder of 13.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 13 to get 13.
Append the next digit (4) from the dividend to 13 and continue with: 134 / 21

Moving on to step 3:
134 divided by 21 is 6 with a remainder of 8.
The next digit of our result is 6. 
Result so far: 6.0
Subtracting 126 from 134 leaves us with 8.
Fetch the next digit (8) from the dividend, attach it to 8 and continue: 88 / 21

Advancing to step 4:
When dividing 88 by 21, we get 4 with a remainder of 4.
Write down 4 as next digit of the result. 
Result so far: 64.0
Deduct 84 from 88 and we're left with 4.
Take the next digit (2) from the dividend and append it to 4, then repeat: 42 / 21

On to step 5:
When dividing 42 by 21, we get 2 with a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 642.0
If we subtract 42 from 42, we get 0.
Bring next digit (3) of the dividend behind the 0 and repeat the process: 3 / 21

Let's proceed to step 6:
3 divided by 21 is 0 with a remainder of 3.
Record the quotient 0 as the next digit in the result. 
Result so far: 6420.0
Subtract 0 from 3 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.

Advancing to step 7:
21 goes into 30 1 times with a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 6420.1
Subtract 21 from 30 to get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Going ahead to step 8:
21 goes into 90 4 times with a remainder of 6.
Record the quotient 4 as the next digit in the result. 
Result so far: 6420.14
If we subtract 84 from 90, we 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.

Let's proceed to step 9:
When dividing 60 by 21, we get 2 with a remainder of 18.
Use 2 as the next digit of our solution. 
Result so far: 6420.142
Subtracting 42 from 60 leaves us 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.

On to step 10:
When dividing 180 by 21, we get 8 with a remainder of 12.
The next digit of our result is 8. 
Result so far: 6420.1428
The remainder is 12 after subtracting 168 from 180.
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 11:
21 can be fit into 120 5 times, resulting in a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 6420.14285
If we take 105 away from 120, we end up 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.

Advancing to step 12:
If we divide 150 by 21, we get 7 and a remainder of 3.
The number 7 becomes the next digit in our result. 
Result so far: 6420.142857
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.

Going ahead to step 13:
If we divide 30 by 21, we get 1 and a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 6420.1428571
The remainder is 9 after subtracting 21 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 14:
If we divide 90 by 21, we get 4 and a remainder of 6.
Write down 4 as next digit of the result. 
Result so far: 6420.14285714
Subtracting 84 from 90 leaves us 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.

After the division, we end up with 6420.14285714 and a remainder of 6e-09.