We're dividing 18419 by 21 
The aim is to understand the frequency of 21 in 18419.

Step 1:
1 divided by 21 is 0 with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Include the next digit (8) from the dividend after 1, then repeat: 18 / 21

On to step 2:
18 divided by 21 is 0 with a remainder of 18.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 18 after subtracting 0 from 18.
Bring next digit (4) of the dividend behind the 18 and repeat the process: 184 / 21

On to step 3:
21 can be fit into 184 8 times, resulting in a remainder of 16.
The number 8 becomes the next digit in our result. 
Result so far: 8.0
If we take 168 away from 184, we end up with 16.
Fetch the next digit (1) from the dividend, attach it to 16 and continue: 161 / 21

Let's proceed to step 4:
The number 21 fits into 161 7 times, leaving a remainder of 14.
Write down 7 as next digit of the result. 
Result so far: 87.0
Subtracting 147 from 161 leaves us with 14.
Include the next digit (9) from the dividend after 14, then repeat: 149 / 21

Let's proceed to step 5:
The number 21 fits into 149 7 times, leaving a remainder of 2.
Record the quotient 7 as the next digit in the result. 
Result so far: 877.0
If we subtract 147 from 149, 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.

Let's proceed to step 6:
If we divide 20 by 21, we get 0 and a remainder of 20.
The next digit of our result is 0. 
Result so far: 877.0
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 7:
21 goes into 200 9 times with a remainder of 11.
Put 9 as the next digit of the answer. 
Result so far: 877.09
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 8:
110 divided by 21 is 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 877.095
The remainder is 5 after subtracting 105 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 9:
The number 21 fits into 50 2 times, leaving a remainder of 8.
The next digit of our result is 2. 
Result so far: 877.0952
The remainder is 8 after subtracting 42 from 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 10:
When dividing 80 by 21, we get 3 with a remainder of 17.
The next digit of our result is 3. 
Result so far: 877.09523
Subtract 63 from 80 to get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Going ahead to step 11:
When dividing 170 by 21, we get 8 with a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 877.095238
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.

Advancing to step 12:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 877.095238
Subtracting 0 from 20 leaves us 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.

Going ahead to step 13:
The number 21 fits into 200 9 times, leaving a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 877.09523809
The remainder is 11 after subtracting 189 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

The quotient of the division is 877.09523809, and the remainder is 1.1e-08.