Let's divide 646399 by 12
Let's see how many times 12 fits into 646399.

On to step 1:
When dividing 6 by 12, we get 0 with a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Bring next digit (4) of the dividend behind the 6 and repeat the process: 64 / 12

Going ahead to step 2:
64 divided by 12 is 5 with a remainder of 4.
The next digit of our result is 5. 
Result so far: 5.0
If we take 60 away from 64, we end up with 4.
Take the next digit (6) from the dividend and append it to 4, then repeat: 46 / 12

Moving on to step 3:
If we divide 46 by 12, we get 3 and a remainder of 10.
The next digit of our result is 3. 
Result so far: 53.0
If we take 36 away from 46, we end up with 10.
Grab the next digit (3) from the dividend, add it to 10, then carry on: 103 / 12

Let's proceed to step 4:
If we divide 103 by 12, we get 8 and a remainder of 7.
Write down 8 as next digit of the result. 
Result so far: 538.0
Subtract 96 from 103 to get 7.
Grab the next digit (9) from the dividend, add it to 7, then carry on: 79 / 12

On to step 5:
79 divided by 12 is 6 with a remainder of 7.
Record the quotient 6 as the next digit in the result. 
Result so far: 5386.0
Deduct 72 from 79 and we're left with 7.
Grab the next digit (9) from the dividend, add it to 7, then carry on: 79 / 12

Going ahead to step 6:
79 divided by 12 is 6 with a remainder of 7.
Use 6 as the next digit of our solution. 
Result so far: 53866.0
Subtract 72 from 79 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

On to step 7:
If we divide 70 by 12, we get 5 and a remainder of 10.
Record the quotient 5 as the next digit in the result. 
Result so far: 53866.5
Subtract 60 from 70 to 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 8:
When dividing 100 by 12, we get 8 with a remainder of 4.
Record the quotient 8 as the next digit in the result. 
Result so far: 53866.58
If we subtract 96 from 100, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Moving on to step 9:
40 divided by 12 is 3 with a remainder of 4.
Write down 3 as next digit of the result. 
Result so far: 53866.583
If we subtract 36 from 40, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 10:
If we divide 40 by 12, we get 3 and a remainder of 4.
Record the quotient 3 as the next digit in the result. 
Result so far: 53866.5833
The remainder is 4 after subtracting 36 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

In conclusion, the division gives 53866.5833 with a balance of 4e-05.