We divide 363799 by 21
The aim is to understand the frequency of 21 in 363799.

Advancing to step 1:
3 divided by 21 is 0 with a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 3 after subtracting 0 from 3.
Fetch the next digit (6) from the dividend, attach it to 3 and continue: 36 / 21

Moving on to step 2:
The number 21 fits into 36 1 times, leaving a remainder of 15.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 21 away from 36, we end up with 15.
Grab the next digit (3) from the dividend, add it to 15, then carry on: 153 / 21

On to step 3:
The number 21 fits into 153 7 times, leaving a remainder of 6.
Put 7 as the next digit of the answer. 
Result so far: 17.0
Subtract 147 from 153 to get 6.
Bring next digit (7) of the dividend behind the 6 and repeat the process: 67 / 21

Step 4:
The number 21 fits into 67 3 times, leaving a remainder of 4.
Use 3 as the next digit of our solution. 
Result so far: 173.0
Deduct 63 from 67 and we're left with 4.
Bring next digit (9) of the dividend behind the 4 and repeat the process: 49 / 21

Step 5:
If we divide 49 by 21, we get 2 and a remainder of 7.
Put 2 as the next digit of the answer. 
Result so far: 1732.0
Subtract 42 from 49 to get 7.
Take the next digit (9) from the dividend and append it to 7, then repeat: 79 / 21

On to step 6:
The number 21 fits into 79 3 times, leaving a remainder of 16.
The number 3 becomes the next digit in our result. 
Result so far: 17323.0
If we subtract 63 from 79, we get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Step 7:
21 can be fit into 160 7 times, resulting in a remainder of 13.
Use 7 as the next digit of our solution. 
Result so far: 17323.7
Subtracting 147 from 160 leaves us 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.

Advancing to step 8:
21 can be fit into 130 6 times, resulting in a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 17323.76
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.

Moving on to step 9:
21 can be fit into 40 1 times, resulting in a remainder of 19.
The next digit of our result is 1. 
Result so far: 17323.761
If we take 21 away from 40, we end up with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Let's proceed to step 10:
190 divided by 21 is 9 with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 17323.7619
Subtract 189 from 190 to get 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.
Use 0 as the next digit of our solution. 
Result so far: 17323.7619
Subtract 0 from 10 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 12:
21 goes into 100 4 times with a remainder of 16.
Write down 4 as next digit of the result. 
Result so far: 17323.761904
Subtract 84 from 100 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 13:
21 goes into 160 7 times with a remainder of 13.
Write down 7 as next digit of the result. 
Result so far: 17323.7619047
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.

Going ahead to step 14:
When dividing 130 by 21, we get 6 with a remainder of 4.
Use 6 as the next digit of our solution. 
Result so far: 17323.76190476
Subtract 126 from 130 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

In conclusion, the division gives 17323.76190476 with a balance of 4e-09.