Let's divide 266316 by 21
The aim is to understand the frequency of 21 in 266316.

Moving on to step 1:
21 goes into 2 0 times with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Take the next digit (6) from the dividend and append it to 2, then repeat: 26 / 21

Moving on to step 2:
The number 21 fits into 26 1 times, leaving a remainder of 5.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Deduct 21 from 26 and we're left with 5.
Append the next digit (6) from the dividend to 5 and continue with: 56 / 21

Let's proceed to step 3:
21 goes into 56 2 times with a remainder of 14.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
Subtracting 42 from 56 leaves us with 14.
Take the next digit (3) from the dividend and append it to 14, then repeat: 143 / 21

Going ahead to step 4:
143 divided by 21 is 6 with a remainder of 17.
Record the quotient 6 as the next digit in the result. 
Result so far: 126.0
Subtracting 126 from 143 leaves us with 17.
Bring next digit (1) of the dividend behind the 17 and repeat the process: 171 / 21

Advancing to step 5:
21 goes into 171 8 times with a remainder of 3.
The next digit of our result is 8. 
Result so far: 1268.0
If we take 168 away from 171, we end up with 3.
Take the next digit (6) from the dividend and append it to 3, then repeat: 36 / 21

Step 6:
When dividing 36 by 21, we get 1 with a remainder of 15.
Write down 1 as next digit of the result. 
Result so far: 12681.0
Deduct 21 from 36 and we're left 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.

Going ahead to step 7:
The number 21 fits into 150 7 times, leaving a remainder of 3.
The number 7 becomes the next digit in our result. 
Result so far: 12681.7
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.

Going ahead to step 8:
21 can be fit into 30 1 times, resulting in a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 12681.71
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 9:
When dividing 90 by 21, we get 4 with a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 12681.714
Deduct 84 from 90 and we're left 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.

On to step 10:
21 goes into 60 2 times with a remainder of 18.
Put 2 as the next digit of the answer. 
Result so far: 12681.7142
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.

Going ahead to step 11:
180 divided by 21 is 8 with a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 12681.71428
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.

Moving on to step 12:
120 divided by 21 is 5 with a remainder of 15.
Put 5 as the next digit of the answer. 
Result so far: 12681.714285
Subtract 105 from 120 to get 15.
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 13:
21 can be fit into 150 7 times, resulting in a remainder of 3.
Put 7 as the next digit of the answer. 
Result so far: 12681.7142857
If we subtract 147 from 150, we 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.

Step 14:
When dividing 30 by 21, we get 1 with a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 12681.71428571
Subtracting 21 from 30 leaves us 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.

Our division results in 12681.71428571 with a remaining 9e-09.