Let's divide 840420 by 86
We want to divide 840420 by 86.

Going ahead to step 1:
The number 86 fits into 8 0 times, leaving a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Include the next digit (4) from the dividend after 8, then repeat: 84 / 86

Let's proceed to step 2:
The number 86 fits into 84 0 times, leaving a remainder of 84.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 84 to get 84.
Bring next digit (0) of the dividend behind the 84 and repeat the process: 840 / 86

Advancing to step 3:
86 can be fit into 840 9 times, resulting in a remainder of 66.
Record the quotient 9 as the next digit in the result. 
Result so far: 9.0
Deduct 774 from 840 and we're left with 66.
Take the next digit (4) from the dividend and append it to 66, then repeat: 664 / 86

Step 4:
86 goes into 664 7 times with a remainder of 62.
Use 7 as the next digit of our solution. 
Result so far: 97.0
Subtracting 602 from 664 leaves us with 62.
Fetch the next digit (2) from the dividend, attach it to 62 and continue: 622 / 86

Let's proceed to step 5:
622 divided by 86 is 7 with a remainder of 20.
Record the quotient 7 as the next digit in the result. 
Result so far: 977.0
The remainder is 20 after subtracting 602 from 622.
Append the next digit (0) from the dividend to 20 and continue with: 200 / 86

Advancing to step 6:
86 can be fit into 200 2 times, resulting in a remainder of 28.
Write down 2 as next digit of the result. 
Result so far: 9772.0
Subtracting 172 from 200 leaves us with 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Step 7:
280 divided by 86 is 3 with a remainder of 22.
Record the quotient 3 as the next digit in the result. 
Result so far: 9772.3
If we take 258 away from 280, we end up with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Let's proceed to step 8:
If we divide 220 by 86, we get 2 and a remainder of 48.
Put 2 as the next digit of the answer. 
Result so far: 9772.32
If we subtract 172 from 220, we get 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

On to step 9:
480 divided by 86 is 5 with a remainder of 50.
Write down 5 as next digit of the result. 
Result so far: 9772.325
Subtracting 430 from 480 leaves us with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 10:
500 divided by 86 is 5 with a remainder of 70.
Record the quotient 5 as the next digit in the result. 
Result so far: 9772.3255
If we subtract 430 from 500, we get 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

The final outcome is 9772.3255, with a leftover of 0.0007.