39400327 ÷ 129 
We want to figure out the number of times 39400327 can be divided by 129.

On to step 1:
When dividing 3 by 129, we get 0 with a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 129

Going ahead to step 2:
129 can be fit into 39 0 times, resulting in a remainder of 39.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 39, we get 39.
Grab the next digit (4) from the dividend, add it to 39, then carry on: 394 / 129

On to step 3:
394 divided by 129 is 3 with a remainder of 7.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
Subtracting 387 from 394 leaves us with 7.
Grab the next digit (0) from the dividend, add it to 7, then carry on: 70 / 129

Moving on to step 4:
70 divided by 129 is 0 with a remainder of 70.
Record the quotient 0 as the next digit in the result. 
Result so far: 30.0
Deduct 0 from 70 and we're left with 70.
Take the next digit (0) from the dividend and append it to 70, then repeat: 700 / 129

Step 5:
If we divide 700 by 129, we get 5 and a remainder of 55.
The next digit of our result is 5. 
Result so far: 305.0
If we subtract 645 from 700, we get 55.
Bring next digit (3) of the dividend behind the 55 and repeat the process: 553 / 129

Let's proceed to step 6:
553 divided by 129 is 4 with a remainder of 37.
Record the quotient 4 as the next digit in the result. 
Result so far: 3054.0
Subtract 516 from 553 to get 37.
Grab the next digit (2) from the dividend, add it to 37, then carry on: 372 / 129

Moving on to step 7:
The number 129 fits into 372 2 times, leaving a remainder of 114.
Use 2 as the next digit of our solution. 
Result so far: 30542.0
Subtract 258 from 372 to get 114.
Include the next digit (7) from the dividend after 114, then repeat: 1147 / 129

Moving on to step 8:
129 can be fit into 1147 8 times, resulting in a remainder of 115.
The next digit of our result is 8. 
Result so far: 305428.0
The remainder is 115 after subtracting 1032 from 1147.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1150, and continue the process.

Going ahead to step 9:
129 can be fit into 1150 8 times, resulting in a remainder of 118.
Write down 8 as next digit of the result. 
Result so far: 305428.8
Subtracting 1032 from 1150 leaves us with 118.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1180, and continue the process.

Going ahead to step 10:
When dividing 1180 by 129, we get 9 with a remainder of 19.
The next digit of our result is 9. 
Result so far: 305428.89
The remainder is 19 after subtracting 1161 from 1180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Advancing to step 11:
If we divide 190 by 129, we get 1 and a remainder of 61.
Write down 1 as next digit of the result. 
Result so far: 305428.891
Deduct 129 from 190 and we're left with 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Moving on to step 12:
When dividing 610 by 129, we get 4 with a remainder of 94.
Write down 4 as next digit of the result. 
Result so far: 305428.8914
Subtracting 516 from 610 leaves us with 94.
Since there are no more digits in the dividend, we add a zero to the remainder making it 940, and continue the process.

On to step 13:
129 goes into 940 7 times with a remainder of 37.
Use 7 as the next digit of our solution. 
Result so far: 305428.89147
If we take 903 away from 940, we end up with 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Let's proceed to step 14:
129 can be fit into 370 2 times, resulting in a remainder of 112.
Put 2 as the next digit of the answer. 
Result so far: 305428.891472
Subtracting 258 from 370 leaves us with 112.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1120, and continue the process.

Going ahead to step 15:
When dividing 1120 by 129, we get 8 with a remainder of 88.
Record the quotient 8 as the next digit in the result. 
Result so far: 305428.8914728
The remainder is 88 after subtracting 1032 from 1120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

Advancing to step 16:
129 can be fit into 880 6 times, resulting in a remainder of 106.
Write down 6 as next digit of the result. 
Result so far: 305428.89147286
Subtract 774 from 880 to get 106.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1060, and continue the process.

Our division results in 305428.89147286 with a remaining 1.06e-07.