Let's divide 17391 by 40
Let's see how many times 40 fits into 17391.

Moving on to step 1:
When dividing 1 by 40, we get 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Take the next digit (7) from the dividend and append it to 1, then repeat: 17 / 40

On to step 2:
40 can be fit into 17 0 times, resulting in a remainder of 17.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 17 to get 17.
Take the next digit (3) from the dividend and append it to 17, then repeat: 173 / 40

Advancing to step 3:
The number 40 fits into 173 4 times, leaving a remainder of 13.
Put 4 as the next digit of the answer. 
Result so far: 4.0
If we take 160 away from 173, we end up with 13.
Grab the next digit (9) from the dividend, add it to 13, then carry on: 139 / 40

On to step 4:
40 goes into 139 3 times with a remainder of 19.
The number 3 becomes the next digit in our result. 
Result so far: 43.0
Deduct 120 from 139 and we're left with 19.
Include the next digit (1) from the dividend after 19, then repeat: 191 / 40

Moving on to step 5:
The number 40 fits into 191 4 times, leaving a remainder of 31.
Use 4 as the next digit of our solution. 
Result so far: 434.0
The remainder is 31 after subtracting 160 from 191.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Advancing to step 6:
When dividing 310 by 40, we get 7 with a remainder of 30.
Put 7 as the next digit of the answer. 
Result so far: 434.7
Subtracting 280 from 310 leaves us 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.

Advancing to step 7:
40 can be fit into 300 7 times, resulting in a remainder of 20.
The next digit of our result is 7. 
Result so far: 434.77
If we subtract 280 from 300, we get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

In conclusion, the division gives 434.77 with a balance of 0.02.