We divide 393458 by 17
We want to figure out the number of times 393458 can be divided by 17.

Moving on to step 1:
The number 17 fits into 3 0 times, leaving a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Take the next digit (9) from the dividend and append it to 3, then repeat: 39 / 17

Step 2:
17 goes into 39 2 times with a remainder of 5.
Write down 2 as next digit of the result. 
Result so far: 2.0
Deduct 34 from 39 and we're left with 5.
Take the next digit (3) from the dividend and append it to 5, then repeat: 53 / 17

Moving on to step 3:
When dividing 53 by 17, we get 3 with a remainder of 2.
The next digit of our result is 3. 
Result so far: 23.0
Deduct 51 from 53 and we're left with 2.
Take the next digit (4) from the dividend and append it to 2, then repeat: 24 / 17

Advancing to step 4:
17 goes into 24 1 times with a remainder of 7.
Record the quotient 1 as the next digit in the result. 
Result so far: 231.0
Subtract 17 from 24 to get 7.
Take the next digit (5) from the dividend and append it to 7, then repeat: 75 / 17

Going ahead to step 5:
The number 17 fits into 75 4 times, leaving a remainder of 7.
The next digit of our result is 4. 
Result so far: 2314.0
If we take 68 away from 75, we end up with 7.
Append the next digit (8) from the dividend to 7 and continue with: 78 / 17

Let's proceed to step 6:
78 divided by 17 is 4 with a remainder of 10.
Put 4 as the next digit of the answer. 
Result so far: 23144.0
Subtracting 68 from 78 leaves us with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 7:
17 goes into 100 5 times with a remainder of 15.
Write down 5 as next digit of the result. 
Result so far: 23144.5
If we subtract 85 from 100, we get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 8:
The number 17 fits into 150 8 times, leaving a remainder of 14.
The number 8 becomes the next digit in our result. 
Result so far: 23144.58
The remainder is 14 after subtracting 136 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Advancing to step 9:
When dividing 140 by 17, we get 8 with a remainder of 4.
Write down 8 as next digit of the result. 
Result so far: 23144.588
Subtracting 136 from 140 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 quotient of the division is 23144.588, and the remainder is 0.0004.