Let's divide 399144 by 23
We want to divide 399144 by 23.

Going ahead to step 1:
The number 23 fits into 3 0 times, leaving a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Append the next digit (9) from the dividend to 3 and continue with: 39 / 23

Going ahead to step 2:
39 divided by 23 is 1 with a remainder of 16.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtracting 23 from 39 leaves us with 16.
Append the next digit (9) from the dividend to 16 and continue with: 169 / 23

On to step 3:
If we divide 169 by 23, we get 7 and a remainder of 8.
Record the quotient 7 as the next digit in the result. 
Result so far: 17.0
If we subtract 161 from 169, we get 8.
Grab the next digit (1) from the dividend, add it to 8, then carry on: 81 / 23

Moving on to step 4:
81 divided by 23 is 3 with a remainder of 12.
Put 3 as the next digit of the answer. 
Result so far: 173.0
If we take 69 away from 81, we end up with 12.
Grab the next digit (4) from the dividend, add it to 12, then carry on: 124 / 23

Step 5:
The number 23 fits into 124 5 times, leaving a remainder of 9.
Record the quotient 5 as the next digit in the result. 
Result so far: 1735.0
Subtracting 115 from 124 leaves us with 9.
Include the next digit (4) from the dividend after 9, then repeat: 94 / 23

Let's proceed to step 6:
23 can be fit into 94 4 times, resulting in a remainder of 2.
The number 4 becomes the next digit in our result. 
Result so far: 17354.0
The remainder is 2 after subtracting 92 from 94.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Going ahead to step 7:
If we divide 20 by 23, we get 0 and a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 17354.0
Subtracting 0 from 20 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Step 8:
23 goes into 200 8 times with a remainder of 16.
Write down 8 as next digit of the result. 
Result so far: 17354.08
Deduct 184 from 200 and we're left with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Going ahead to step 9:
The number 23 fits into 160 6 times, leaving a remainder of 22.
Put 6 as the next digit of the answer. 
Result so far: 17354.086
If we subtract 138 from 160, we get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Going ahead to step 10:
If we divide 220 by 23, we get 9 and a remainder of 13.
Record the quotient 9 as the next digit in the result. 
Result so far: 17354.0869
The remainder is 13 after subtracting 207 from 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Step 11:
23 can be fit into 130 5 times, resulting in a remainder of 15.
The next digit of our result is 5. 
Result so far: 17354.08695
The remainder is 15 after subtracting 115 from 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

On to step 12:
When dividing 150 by 23, we get 6 with a remainder of 12.
Put 6 as the next digit of the answer. 
Result so far: 17354.086956
Deduct 138 from 150 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 13:
When dividing 120 by 23, we get 5 with a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 17354.0869565
Subtract 115 from 120 to 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.

Moving on to step 14:
If we divide 50 by 23, we get 2 and a remainder of 4.
Put 2 as the next digit of the answer. 
Result so far: 17354.08695652
Subtracting 46 from 50 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

The final result is 17354.08695652 with a remainder of 4e-09.