Let's divide 640366 by 12
We're looking to find how many times 12 goes into 640366.

Moving on to step 1:
If we divide 6 by 12, we get 0 and a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Include the next digit (4) from the dividend after 6, then repeat: 64 / 12

Advancing to step 2:
The number 12 fits into 64 5 times, leaving a remainder of 4.
The next digit of our result is 5. 
Result so far: 5.0
Deduct 60 from 64 and we're left with 4.
Include the next digit (0) from the dividend after 4, then repeat: 40 / 12

Advancing to step 3:
12 can be fit into 40 3 times, resulting in a remainder of 4.
Use 3 as the next digit of our solution. 
Result so far: 53.0
Subtracting 36 from 40 leaves us with 4.
Grab the next digit (3) from the dividend, add it to 4, then carry on: 43 / 12

Going ahead to step 4:
12 can be fit into 43 3 times, resulting in a remainder of 7.
The number 3 becomes the next digit in our result. 
Result so far: 533.0
If we take 36 away from 43, we end up with 7.
Include the next digit (6) from the dividend after 7, then repeat: 76 / 12

Moving on to step 5:
When dividing 76 by 12, we get 6 with a remainder of 4.
The next digit of our result is 6. 
Result so far: 5336.0
If we subtract 72 from 76, we get 4.
Grab the next digit (6) from the dividend, add it to 4, then carry on: 46 / 12

On to step 6:
When dividing 46 by 12, we get 3 with a remainder of 10.
The number 3 becomes the next digit in our result. 
Result so far: 53363.0
The remainder is 10 after subtracting 36 from 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 7:
12 goes into 100 8 times with a remainder of 4.
Use 8 as the next digit of our solution. 
Result so far: 53363.8
Deduct 96 from 100 and we're left with 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 8:
12 can be fit into 40 3 times, resulting in a remainder of 4.
Write down 3 as next digit of the result. 
Result so far: 53363.83
Subtract 36 from 40 to 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 9:
When dividing 40 by 12, we get 3 with a remainder of 4.
The number 3 becomes the next digit in our result. 
Result so far: 53363.833
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.

The final outcome is 53363.833, with a leftover of 0.0004.