398910 ÷ 23 
The aim is to understand the frequency of 23 in 398910.

On to step 1:
The number 23 fits into 3 0 times, leaving a remainder of 3.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 3 after subtracting 0 from 3.
Append the next digit (9) from the dividend to 3 and continue with: 39 / 23

Let's proceed to step 2:
When dividing 39 by 23, we get 1 with a remainder of 16.
The next digit of our result is 1. 
Result so far: 1.0
Deduct 23 from 39 and we're left with 16.
Append the next digit (8) from the dividend to 16 and continue with: 168 / 23

Going ahead to step 3:
If we divide 168 by 23, we get 7 and a remainder of 7.
The number 7 becomes the next digit in our result. 
Result so far: 17.0
If we subtract 161 from 168, we get 7.
Append the next digit (9) from the dividend to 7 and continue with: 79 / 23

Advancing to step 4:
23 goes into 79 3 times with a remainder of 10.
Write down 3 as next digit of the result. 
Result so far: 173.0
The remainder is 10 after subtracting 69 from 79.
Bring next digit (1) of the dividend behind the 10 and repeat the process: 101 / 23

Step 5:
If we divide 101 by 23, we get 4 and a remainder of 9.
Write down 4 as next digit of the result. 
Result so far: 1734.0
If we subtract 92 from 101, we get 9.
Take the next digit (0) from the dividend and append it to 9, then repeat: 90 / 23

Going ahead to step 6:
If we divide 90 by 23, we get 3 and a remainder of 21.
The next digit of our result is 3. 
Result so far: 17343.0
Deduct 69 from 90 and we're left with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Let's proceed to step 7:
23 goes into 210 9 times with a remainder of 3.
Record the quotient 9 as the next digit in the result. 
Result so far: 17343.9
If we subtract 207 from 210, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Advancing to step 8:
30 divided by 23 is 1 with a remainder of 7.
Write down 1 as next digit of the result. 
Result so far: 17343.91
If we subtract 23 from 30, we get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 9:
If we divide 70 by 23, we get 3 and a remainder of 1.
Use 3 as the next digit of our solution. 
Result so far: 17343.913
The remainder is 1 after subtracting 69 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Advancing to step 10:
23 can be fit into 10 0 times, resulting in a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 17343.913
Subtracting 0 from 10 leaves us with 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 11:
100 divided by 23 is 4 with a remainder of 8.
Use 4 as the next digit of our solution. 
Result so far: 17343.91304
Subtract 92 from 100 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.

Going ahead to step 12:
When dividing 80 by 23, we get 3 with a remainder of 11.
Use 3 as the next digit of our solution. 
Result so far: 17343.913043
If we subtract 69 from 80, we get 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 13:
23 can be fit into 110 4 times, resulting in a remainder of 18.
Put 4 as the next digit of the answer. 
Result so far: 17343.9130434
Subtract 92 from 110 to get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 14:
The number 23 fits into 180 7 times, leaving a remainder of 19.
Record the quotient 7 as the next digit in the result. 
Result so far: 17343.91304347
Subtract 161 from 180 to get 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

The final result is 17343.91304347 with a remainder of 1.9e-08.