Let's divide 722711 by 21
The aim is to understand the frequency of 21 in 722711.

Step 1:
If we divide 7 by 21, we get 0 and a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Append the next digit (2) from the dividend to 7 and continue with: 72 / 21

Step 2:
21 can be fit into 72 3 times, resulting in a remainder of 9.
The next digit of our result is 3. 
Result so far: 3.0
Deduct 63 from 72 and we're left with 9.
Grab the next digit (2) from the dividend, add it to 9, then carry on: 92 / 21

Going ahead to step 3:
21 goes into 92 4 times with a remainder of 8.
Write down 4 as next digit of the result. 
Result so far: 34.0
The remainder is 8 after subtracting 84 from 92.
Fetch the next digit (7) from the dividend, attach it to 8 and continue: 87 / 21

Let's proceed to step 4:
87 divided by 21 is 4 with a remainder of 3.
The number 4 becomes the next digit in our result. 
Result so far: 344.0
If we take 84 away from 87, we end up with 3.
Fetch the next digit (1) from the dividend, attach it to 3 and continue: 31 / 21

Step 5:
If we divide 31 by 21, we get 1 and a remainder of 10.
Put 1 as the next digit of the answer. 
Result so far: 3441.0
Subtracting 21 from 31 leaves us with 10.
Bring next digit (1) of the dividend behind the 10 and repeat the process: 101 / 21

Moving on to step 6:
101 divided by 21 is 4 with a remainder of 17.
The next digit of our result is 4. 
Result so far: 34414.0
If we take 84 away from 101, we end up with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 7:
The number 21 fits into 170 8 times, leaving a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 34414.8
The remainder is 2 after subtracting 168 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Advancing to step 8:
21 goes into 20 0 times with a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 34414.8
Deduct 0 from 20 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Let's proceed to step 9:
When dividing 200 by 21, we get 9 with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 34414.809
Deduct 189 from 200 and we're left with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Going ahead to step 10:
When dividing 110 by 21, we get 5 with a remainder of 5.
The next digit of our result is 5. 
Result so far: 34414.8095
If we subtract 105 from 110, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 11:
The number 21 fits into 50 2 times, leaving a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 34414.80952
Deduct 42 from 50 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 12:
21 can be fit into 80 3 times, resulting in a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 34414.809523
The remainder is 17 after subtracting 63 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Moving on to step 13:
If we divide 170 by 21, we get 8 and a remainder of 2.
The next digit of our result is 8. 
Result so far: 34414.8095238
If we subtract 168 from 170, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 14:
21 goes into 20 0 times with a remainder of 20.
The next digit of our result is 0. 
Result so far: 34414.8095238
If we subtract 0 from 20, we get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

In conclusion, the division gives 34414.8095238 with a balance of 2e-08.