We look at the division of 400669 by 12 
We want to divide 400669 by 12.

Advancing to step 1:
The number 12 fits into 4 0 times, leaving a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Append the next digit (0) from the dividend to 4 and continue with: 40 / 12

Moving on to step 2:
12 can be fit into 40 3 times, resulting in a remainder of 4.
The next digit of our result is 3. 
Result so far: 3.0
Deduct 36 from 40 and we're left with 4.
Append the next digit (0) from the dividend to 4 and continue with: 40 / 12

Going ahead to step 3:
When dividing 40 by 12, we get 3 with a remainder of 4.
Record the quotient 3 as the next digit in the result. 
Result so far: 33.0
Subtracting 36 from 40 leaves us with 4.
Bring next digit (6) of the dividend behind the 4 and repeat the process: 46 / 12

Moving on to step 4:
46 divided by 12 is 3 with a remainder of 10.
Record the quotient 3 as the next digit in the result. 
Result so far: 333.0
Subtract 36 from 46 to get 10.
Append the next digit (6) from the dividend to 10 and continue with: 106 / 12

Let's proceed to step 5:
When dividing 106 by 12, we get 8 with a remainder of 10.
Use 8 as the next digit of our solution. 
Result so far: 3338.0
The remainder is 10 after subtracting 96 from 106.
Fetch the next digit (9) from the dividend, attach it to 10 and continue: 109 / 12

Moving on to step 6:
When dividing 109 by 12, we get 9 with a remainder of 1.
Write down 9 as next digit of the result. 
Result so far: 33389.0
If we take 108 away from 109, we end up with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Moving on to step 7:
When dividing 10 by 12, we get 0 with a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 33389.0
If we take 0 away from 10, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 8:
If we divide 100 by 12, we get 8 and a remainder of 4.
Write down 8 as next digit of the result. 
Result so far: 33389.08
If we take 96 away from 100, we end up 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.

On to step 9:
40 divided by 12 is 3 with a remainder of 4.
The number 3 becomes the next digit in our result. 
Result so far: 33389.083
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.

Moving on to step 10:
40 divided by 12 is 3 with a remainder of 4.
The next digit of our result is 3. 
Result so far: 33389.0833
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.

The final outcome is 33389.0833, with a leftover of 4e-05.