We look at the division of 309923 by 25 
We want to divide 309923 by 25.

Moving on to step 1:
25 can be fit into 3 0 times, resulting in a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Fetch the next digit (0) from the dividend, attach it to 3 and continue: 30 / 25

Moving on to step 2:
The number 25 fits into 30 1 times, leaving a remainder of 5.
Write down 1 as next digit of the result. 
Result so far: 1.0
The remainder is 5 after subtracting 25 from 30.
Include the next digit (9) from the dividend after 5, then repeat: 59 / 25

Step 3:
When dividing 59 by 25, we get 2 with a remainder of 9.
Put 2 as the next digit of the answer. 
Result so far: 12.0
Subtract 50 from 59 to get 9.
Fetch the next digit (9) from the dividend, attach it to 9 and continue: 99 / 25

On to step 4:
If we divide 99 by 25, we get 3 and a remainder of 24.
The next digit of our result is 3. 
Result so far: 123.0
Subtracting 75 from 99 leaves us with 24.
Take the next digit (2) from the dividend and append it to 24, then repeat: 242 / 25

Let's proceed to step 5:
25 goes into 242 9 times with a remainder of 17.
Write down 9 as next digit of the result. 
Result so far: 1239.0
The remainder is 17 after subtracting 225 from 242.
Include the next digit (3) from the dividend after 17, then repeat: 173 / 25

Advancing to step 6:
25 can be fit into 173 6 times, resulting in a remainder of 23.
Put 6 as the next digit of the answer. 
Result so far: 12396.0
If we take 150 away from 173, we end up with 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Moving on to step 7:
When dividing 230 by 25, we get 9 with a remainder of 5.
The number 9 becomes the next digit in our result. 
Result so far: 12396.9
The remainder is 5 after subtracting 225 from 230.
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 8:
The number 25 fits into 50 2 times, leaving a remainder of 0.
Write down 2 as next digit of the result. 
Result so far: 12396.92
Subtract 50 from 50 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 9:
If we divide 0 by 25, we get 0 and a remainder of 0.
The next digit of our result is 0. 
Result so far: 12396.92
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 10:
25 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 12396.92
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 12396.92 with a remainder of 0.0.