Let's divide 854884 by 21
The aim is to understand the frequency of 21 in 854884.

Going ahead to step 1:
8 divided by 21 is 0 with a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Append the next digit (5) from the dividend to 8 and continue with: 85 / 21

Going ahead to step 2:
21 can be fit into 85 4 times, resulting in a remainder of 1.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
Subtracting 84 from 85 leaves us with 1.
Fetch the next digit (4) from the dividend, attach it to 1 and continue: 14 / 21

On to step 3:
21 can be fit into 14 0 times, resulting in a remainder of 14.
Use 0 as the next digit of our solution. 
Result so far: 40.0
Subtract 0 from 14 to get 14.
Append the next digit (8) from the dividend to 14 and continue with: 148 / 21

On to step 4:
The number 21 fits into 148 7 times, leaving a remainder of 1.
Put 7 as the next digit of the answer. 
Result so far: 407.0
If we subtract 147 from 148, we get 1.
Grab the next digit (8) from the dividend, add it to 1, then carry on: 18 / 21

Step 5:
21 can be fit into 18 0 times, resulting in a remainder of 18.
Put 0 as the next digit of the answer. 
Result so far: 4070.0
If we take 0 away from 18, we end up with 18.
Bring next digit (4) of the dividend behind the 18 and repeat the process: 184 / 21

Let's proceed to step 6:
If we divide 184 by 21, we get 8 and a remainder of 16.
Put 8 as the next digit of the answer. 
Result so far: 40708.0
Subtracting 168 from 184 leaves us with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 7:
If we divide 160 by 21, we get 7 and a remainder of 13.
Write down 7 as next digit of the result. 
Result so far: 40708.7
If we take 147 away from 160, we end up with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Let's proceed to step 8:
21 goes into 130 6 times with a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 40708.76
The remainder is 4 after subtracting 126 from 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 9:
If we divide 40 by 21, we get 1 and a remainder of 19.
Put 1 as the next digit of the answer. 
Result so far: 40708.761
The remainder is 19 after subtracting 21 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Moving on to step 10:
21 goes into 190 9 times with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 40708.7619
If we take 189 away from 190, we end up with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 11:
When dividing 10 by 21, we get 0 with a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 40708.7619
The remainder is 10 after subtracting 0 from 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 12:
100 divided by 21 is 4 with a remainder of 16.
Use 4 as the next digit of our solution. 
Result so far: 40708.761904
If we take 84 away from 100, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 13:
The number 21 fits into 160 7 times, leaving a remainder of 13.
Put 7 as the next digit of the answer. 
Result so far: 40708.7619047
The remainder is 13 after subtracting 147 from 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Let's proceed to step 14:
If we divide 130 by 21, we get 6 and a remainder of 4.
The next digit of our result is 6. 
Result so far: 40708.76190476
Subtracting 126 from 130 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

After the division, we end up with 40708.76190476 and a remainder of 4e-09.