39903 ÷ 58 
We want to divide 39903 by 58.

Step 1:
If we divide 3 by 58, we get 0 and a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Include the next digit (9) from the dividend after 3, then repeat: 39 / 58

Step 2:
58 can be fit into 39 0 times, resulting in a remainder of 39.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 39 leaves us with 39.
Grab the next digit (9) from the dividend, add it to 39, then carry on: 399 / 58

Advancing to step 3:
When dividing 399 by 58, we get 6 with a remainder of 51.
The number 6 becomes the next digit in our result. 
Result so far: 6.0
If we take 348 away from 399, we end up with 51.
Take the next digit (0) from the dividend and append it to 51, then repeat: 510 / 58

On to step 4:
When dividing 510 by 58, we get 8 with a remainder of 46.
Write down 8 as next digit of the result. 
Result so far: 68.0
Subtract 464 from 510 to get 46.
Take the next digit (3) from the dividend and append it to 46, then repeat: 463 / 58

Going ahead to step 5:
If we divide 463 by 58, we get 7 and a remainder of 57.
Put 7 as the next digit of the answer. 
Result so far: 687.0
Deduct 406 from 463 and we're left with 57.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

Going ahead to step 6:
58 can be fit into 570 9 times, resulting in a remainder of 48.
Use 9 as the next digit of our solution. 
Result so far: 687.9
If we take 522 away from 570, we end up with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Let's proceed to step 7:
480 divided by 58 is 8 with a remainder of 16.
Record the quotient 8 as the next digit in the result. 
Result so far: 687.98
If we subtract 464 from 480, we get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 8:
58 goes into 160 2 times with a remainder of 44.
Record the quotient 2 as the next digit in the result. 
Result so far: 687.982
The remainder is 44 after subtracting 116 from 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 440, and continue the process.

Advancing to step 9:
58 can be fit into 440 7 times, resulting in a remainder of 34.
The next digit of our result is 7. 
Result so far: 687.9827
Deduct 406 from 440 and we're left with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Step 10:
The number 58 fits into 340 5 times, leaving a remainder of 50.
The next digit of our result is 5. 
Result so far: 687.98275
If we subtract 290 from 340, we get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Let's proceed to step 11:
58 goes into 500 8 times with a remainder of 36.
Use 8 as the next digit of our solution. 
Result so far: 687.982758
The remainder is 36 after subtracting 464 from 500.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

On to step 12:
58 can be fit into 360 6 times, resulting in a remainder of 12.
The number 6 becomes the next digit in our result. 
Result so far: 687.9827586
The remainder is 12 after subtracting 348 from 360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 13:
58 can be fit into 120 2 times, resulting in a remainder of 4.
The number 2 becomes the next digit in our result. 
Result so far: 687.98275862
Subtract 116 from 120 to get 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 outcome is 687.98275862, with a leftover of 4e-09.