921488 divided by 21 
The aim is to understand the frequency of 21 in 921488.

Step 1:
21 goes into 9 0 times with a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 9 and we're left with 9.
Bring next digit (2) of the dividend behind the 9 and repeat the process: 92 / 21

Step 2:
92 divided by 21 is 4 with a remainder of 8.
The next digit of our result is 4. 
Result so far: 4.0
If we subtract 84 from 92, we get 8.
Take the next digit (1) from the dividend and append it to 8, then repeat: 81 / 21

Let's proceed to step 3:
81 divided by 21 is 3 with a remainder of 18.
Put 3 as the next digit of the answer. 
Result so far: 43.0
If we subtract 63 from 81, we get 18.
Fetch the next digit (4) from the dividend, attach it to 18 and continue: 184 / 21

Moving on to step 4:
The number 21 fits into 184 8 times, leaving a remainder of 16.
Put 8 as the next digit of the answer. 
Result so far: 438.0
If we take 168 away from 184, we end up with 16.
Include the next digit (8) from the dividend after 16, then repeat: 168 / 21

On to step 5:
21 can be fit into 168 8 times, resulting in a remainder of 0.
The next digit of our result is 8. 
Result so far: 4388.0
The remainder is 0 after subtracting 168 from 168.
Fetch the next digit (8) from the dividend, attach it to 0 and continue: 8 / 21

Step 6:
8 divided by 21 is 0 with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 43880.0
The remainder is 8 after subtracting 0 from 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

On to step 7:
21 goes into 80 3 times with a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 43880.3
If we take 63 away from 80, we end up with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Advancing to step 8:
170 divided by 21 is 8 with a remainder of 2.
The next digit of our result is 8. 
Result so far: 43880.38
Subtracting 168 from 170 leaves us with 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 9:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 43880.38
Subtract 0 from 20 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Moving on to step 10:
200 divided by 21 is 9 with a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 43880.3809
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.

On to step 11:
21 goes into 110 5 times with a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 43880.38095
If we subtract 105 from 110, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 12:
21 can be fit into 50 2 times, resulting in a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 43880.380952
Subtract 42 from 50 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 13:
If we divide 80 by 21, we get 3 and a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 43880.3809523
The remainder is 17 after subtracting 63 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 14:
If we divide 170 by 21, we get 8 and a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 43880.38095238
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.

The quotient of the division is 43880.38095238, and the remainder is 2e-09.