We look at the division of 70133 by 21 
The aim is to understand the frequency of 21 in 70133.

Going ahead to step 1:
21 can be fit into 7 0 times, resulting in 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.
Bring next digit (0) of the dividend behind the 7 and repeat the process: 70 / 21

Moving on to step 2:
When dividing 70 by 21, we get 3 with a remainder of 7.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
Subtracting 63 from 70 leaves us with 7.
Fetch the next digit (1) from the dividend, attach it to 7 and continue: 71 / 21

Going ahead to step 3:
21 goes into 71 3 times with a remainder of 8.
Record the quotient 3 as the next digit in the result. 
Result so far: 33.0
Subtract 63 from 71 to get 8.
Include the next digit (3) from the dividend after 8, then repeat: 83 / 21

Going ahead to step 4:
If we divide 83 by 21, we get 3 and a remainder of 20.
Record the quotient 3 as the next digit in the result. 
Result so far: 333.0
The remainder is 20 after subtracting 63 from 83.
Fetch the next digit (3) from the dividend, attach it to 20 and continue: 203 / 21

Advancing to step 5:
21 goes into 203 9 times with a remainder of 14.
The next digit of our result is 9. 
Result so far: 3339.0
Subtract 189 from 203 to get 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 6:
When dividing 140 by 21, we get 6 with a remainder of 14.
Record the quotient 6 as the next digit in the result. 
Result so far: 3339.6
Subtracting 126 from 140 leaves us with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Moving on to step 7:
21 goes into 140 6 times with a remainder of 14.
Record the quotient 6 as the next digit in the result. 
Result so far: 3339.66
Deduct 126 from 140 and we're left with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

The quotient of the division is 3339.66, and the remainder is 0.014.