846494 ÷ 21 
The aim is to understand the frequency of 21 in 846494.

Going ahead to step 1:
If we divide 8 by 21, we get 0 and a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Take the next digit (4) from the dividend and append it to 8, then repeat: 84 / 21

Advancing to step 2:
The number 21 fits into 84 4 times, leaving a remainder of 0.
Write down 4 as next digit of the result. 
Result so far: 4.0
Subtract 84 from 84 to get 0.
Append the next digit (6) from the dividend to 0 and continue with: 6 / 21

Going ahead to step 3:
21 goes into 6 0 times with a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 40.0
Deduct 0 from 6 and we're left with 6.
Append the next digit (4) from the dividend to 6 and continue with: 64 / 21

Moving on to step 4:
The number 21 fits into 64 3 times, leaving a remainder of 1.
Record the quotient 3 as the next digit in the result. 
Result so far: 403.0
Deduct 63 from 64 and we're left with 1.
Fetch the next digit (9) from the dividend, attach it to 1 and continue: 19 / 21

On to step 5:
If we divide 19 by 21, we get 0 and a remainder of 19.
Record the quotient 0 as the next digit in the result. 
Result so far: 4030.0
Deduct 0 from 19 and we're left with 19.
Bring next digit (4) of the dividend behind the 19 and repeat the process: 194 / 21

Going ahead to step 6:
The number 21 fits into 194 9 times, leaving a remainder of 5.
The number 9 becomes the next digit in our result. 
Result so far: 40309.0
The remainder is 5 after subtracting 189 from 194.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 7:
If we divide 50 by 21, we get 2 and a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 40309.2
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.

On to step 8:
If we divide 80 by 21, we get 3 and a remainder of 17.
The next digit of our result is 3. 
Result so far: 40309.23
If we subtract 63 from 80, we 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 9:
21 can be fit into 170 8 times, resulting in a remainder of 2.
The next digit of our result is 8. 
Result so far: 40309.238
If we take 168 away from 170, we end up 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.

Step 10:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 40309.238
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 11:
When dividing 200 by 21, we get 9 with a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 40309.23809
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.

Let's proceed to step 12:
The number 21 fits into 110 5 times, leaving a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 40309.238095
If we take 105 away from 110, we end up with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 13:
If we divide 50 by 21, we get 2 and a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 40309.2380952
If we subtract 42 from 50, we 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.

On to step 14:
If we divide 80 by 21, we get 3 and a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 40309.23809523
Deduct 63 from 80 and we're left 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.

Our division results in 40309.23809523 with a remaining 1.7e-08.