865239 ÷ 12 
Our goal is to divide 865239 by 12.

On to step 1:
When dividing 8 by 12, we get 0 with a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Grab the next digit (6) from the dividend, add it to 8, then carry on: 86 / 12

Let's proceed to step 2:
12 can be fit into 86 7 times, resulting in a remainder of 2.
Write down 7 as next digit of the result. 
Result so far: 7.0
Subtracting 84 from 86 leaves us with 2.
Append the next digit (5) from the dividend to 2 and continue with: 25 / 12

Let's proceed to step 3:
When dividing 25 by 12, we get 2 with a remainder of 1.
Write down 2 as next digit of the result. 
Result so far: 72.0
Deduct 24 from 25 and we're left with 1.
Grab the next digit (2) from the dividend, add it to 1, then carry on: 12 / 12

Moving on to step 4:
The number 12 fits into 12 1 times, leaving a remainder of 0.
Record the quotient 1 as the next digit in the result. 
Result so far: 721.0
Deduct 12 from 12 and we're left with 0.
Grab the next digit (3) from the dividend, add it to 0, then carry on: 3 / 12

Step 5:
12 can be fit into 3 0 times, resulting in a remainder of 3.
The next digit of our result is 0. 
Result so far: 7210.0
The remainder is 3 after subtracting 0 from 3.
Grab the next digit (9) from the dividend, add it to 3, then carry on: 39 / 12

Let's proceed to step 6:
39 divided by 12 is 3 with a remainder of 3.
Record the quotient 3 as the next digit in the result. 
Result so far: 72103.0
The remainder is 3 after subtracting 36 from 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Going ahead to step 7:
12 can be fit into 30 2 times, resulting in a remainder of 6.
Put 2 as the next digit of the answer. 
Result so far: 72103.2
Subtract 24 from 30 to get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Let's proceed to step 8:
12 can be fit into 60 5 times, resulting in a remainder of 0.
Use 5 as the next digit of our solution. 
Result so far: 72103.25
Subtract 60 from 60 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 9:
12 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 72103.25
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 10:
12 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 72103.25
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 72103.25, with a leftover of 0.0.