We look at the division of 309536 by 86 
We're looking to find how many times 86 goes into 309536.

On to step 1:
3 divided by 86 is 0 with a remainder of 3.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 3, we get 3.
Fetch the next digit (0) from the dividend, attach it to 3 and continue: 30 / 86

Moving on to step 2:
When dividing 30 by 86, we get 0 with a remainder of 30.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 30, we get 30.
Append the next digit (9) from the dividend to 30 and continue with: 309 / 86

Going ahead to step 3:
86 can be fit into 309 3 times, resulting in a remainder of 51.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
If we subtract 258 from 309, we get 51.
Take the next digit (5) from the dividend and append it to 51, then repeat: 515 / 86

On to step 4:
When dividing 515 by 86, we get 5 with a remainder of 85.
Use 5 as the next digit of our solution. 
Result so far: 35.0
The remainder is 85 after subtracting 430 from 515.
Include the next digit (3) from the dividend after 85, then repeat: 853 / 86

Step 5:
If we divide 853 by 86, we get 9 and a remainder of 79.
The number 9 becomes the next digit in our result. 
Result so far: 359.0
Subtract 774 from 853 to get 79.
Take the next digit (6) from the dividend and append it to 79, then repeat: 796 / 86

Step 6:
86 can be fit into 796 9 times, resulting in a remainder of 22.
Put 9 as the next digit of the answer. 
Result so far: 3599.0
Subtracting 774 from 796 leaves us 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.

Advancing to step 7:
220 divided by 86 is 2 with a remainder of 48.
The next digit of our result is 2. 
Result so far: 3599.2
Deduct 172 from 220 and we're left with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Going ahead to step 8:
When dividing 480 by 86, we get 5 with a remainder of 50.
Put 5 as the next digit of the answer. 
Result so far: 3599.25
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.

Moving on to step 9:
The number 86 fits into 500 5 times, leaving a remainder of 70.
Write down 5 as next digit of the result. 
Result so far: 3599.255
Deduct 430 from 500 and we're left with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Our division results in 3599.255 with a remaining 0.007.