We're dividing 339840 by 17 
Our goal is to divide 339840 by 17.

Going ahead to step 1:
If we divide 3 by 17, we get 0 and a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Include the next digit (3) from the dividend after 3, then repeat: 33 / 17

Going ahead to step 2:
When dividing 33 by 17, we get 1 with a remainder of 16.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Deduct 17 from 33 and we're left with 16.
Grab the next digit (9) from the dividend, add it to 16, then carry on: 169 / 17

Advancing to step 3:
When dividing 169 by 17, we get 9 with a remainder of 16.
Put 9 as the next digit of the answer. 
Result so far: 19.0
If we take 153 away from 169, we end up with 16.
Include the next digit (8) from the dividend after 16, then repeat: 168 / 17

Going ahead to step 4:
17 goes into 168 9 times with a remainder of 15.
Record the quotient 9 as the next digit in the result. 
Result so far: 199.0
Deduct 153 from 168 and we're left with 15.
Bring next digit (4) of the dividend behind the 15 and repeat the process: 154 / 17

Let's proceed to step 5:
17 goes into 154 9 times with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 1999.0
If we subtract 153 from 154, we get 1.
Append the next digit (0) from the dividend to 1 and continue with: 10 / 17

On to step 6:
10 divided by 17 is 0 with a remainder of 10.
Write down 0 as next digit of the result. 
Result so far: 19990.0
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 7:
100 divided by 17 is 5 with a remainder of 15.
Use 5 as the next digit of our solution. 
Result so far: 19990.5
The remainder is 15 after subtracting 85 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Let's proceed to step 8:
17 can be fit into 150 8 times, resulting in a remainder of 14.
Write down 8 as next digit of the result. 
Result so far: 19990.58
If we take 136 away from 150, we end up with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Step 9:
When dividing 140 by 17, we get 8 with a remainder of 4.
The next digit of our result is 8. 
Result so far: 19990.588
The remainder is 4 after subtracting 136 from 140.
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 19990.588, with a leftover of 0.0004.