We're dividing 67396 by 21 
The aim is to understand the frequency of 21 in 67396.

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.
Grab the next digit (7) from the dividend, add it to 6, then carry on: 67 / 21

Moving on to step 2:
When dividing 67 by 21, we get 3 with a remainder of 4.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
The remainder is 4 after subtracting 63 from 67.
Bring next digit (3) of the dividend behind the 4 and repeat the process: 43 / 21

Advancing to step 3:
The number 21 fits into 43 2 times, leaving a remainder of 1.
Use 2 as the next digit of our solution. 
Result so far: 32.0
Subtracting 42 from 43 leaves us with 1.
Append the next digit (9) from the dividend to 1 and continue with: 19 / 21

Advancing to step 4:
21 goes into 19 0 times with a remainder of 19.
Write down 0 as next digit of the result. 
Result so far: 320.0
Subtracting 0 from 19 leaves us with 19.
Include the next digit (6) from the dividend after 19, then repeat: 196 / 21

On to step 5:
196 divided by 21 is 9 with a remainder of 7.
The number 9 becomes the next digit in our result. 
Result so far: 3209.0
Deduct 189 from 196 and we're left 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.

Going ahead to step 6:
21 can be fit into 70 3 times, resulting in a remainder of 7.
Use 3 as the next digit of our solution. 
Result so far: 3209.3
If we take 63 away from 70, we end up 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.

On to step 7:
When dividing 70 by 21, we get 3 with a remainder of 7.
Write down 3 as next digit of the result. 
Result so far: 3209.33
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.

In conclusion, the division gives 3209.33 with a balance of 0.007.