We divide 517509 by 42
Let's see how many times 42 fits into 517509.

Advancing to step 1:
42 goes into 5 0 times with a remainder of 5.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Grab the next digit (1) from the dividend, add it to 5, then carry on: 51 / 42

Moving on to step 2:
When dividing 51 by 42, we get 1 with a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtract 42 from 51 to get 9.
Grab the next digit (7) from the dividend, add it to 9, then carry on: 97 / 42

Step 3:
42 goes into 97 2 times with a remainder of 13.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
If we subtract 84 from 97, we get 13.
Take the next digit (5) from the dividend and append it to 13, then repeat: 135 / 42

Let's proceed to step 4:
If we divide 135 by 42, we get 3 and a remainder of 9.
Write down 3 as next digit of the result. 
Result so far: 123.0
The remainder is 9 after subtracting 126 from 135.
Append the next digit (0) from the dividend to 9 and continue with: 90 / 42

Going ahead to step 5:
90 divided by 42 is 2 with a remainder of 6.
Put 2 as the next digit of the answer. 
Result so far: 1232.0
Deduct 84 from 90 and we're left with 6.
Bring next digit (9) of the dividend behind the 6 and repeat the process: 69 / 42

Let's proceed to step 6:
The number 42 fits into 69 1 times, leaving a remainder of 27.
Record the quotient 1 as the next digit in the result. 
Result so far: 12321.0
If we subtract 42 from 69, we get 27.
Since there are no more digits in the dividend, we add a zero to the remainder making it 270, and continue the process.

Going ahead to step 7:
42 can be fit into 270 6 times, resulting in a remainder of 18.
Record the quotient 6 as the next digit in the result. 
Result so far: 12321.6
If we subtract 252 from 270, we 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.

Step 8:
When dividing 180 by 42, we get 4 with a remainder of 12.
Record the quotient 4 as the next digit in the result. 
Result so far: 12321.64
If we subtract 168 from 180, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 9:
When dividing 120 by 42, we get 2 with a remainder of 36.
Use 2 as the next digit of our solution. 
Result so far: 12321.642
The remainder is 36 after subtracting 84 from 120.
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 10:
360 divided by 42 is 8 with a remainder of 24.
Record the quotient 8 as the next digit in the result. 
Result so far: 12321.6428
Subtracting 336 from 360 leaves us with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Moving on to step 11:
When dividing 240 by 42, we get 5 with a remainder of 30.
Record the quotient 5 as the next digit in the result. 
Result so far: 12321.64285
Deduct 210 from 240 and we're left with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Going ahead to step 12:
42 goes into 300 7 times with a remainder of 6.
The next digit of our result is 7. 
Result so far: 12321.642857
The remainder is 6 after subtracting 294 from 300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Going ahead to step 13:
When dividing 60 by 42, we get 1 with a remainder of 18.
Put 1 as the next digit of the answer. 
Result so far: 12321.6428571
Deduct 42 from 60 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Going ahead to step 14:
42 goes into 180 4 times with a remainder of 12.
The number 4 becomes the next digit in our result. 
Result so far: 12321.64285714
The remainder is 12 after subtracting 168 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

The final result is 12321.64285714 with a remainder of 1.2e-08.