We divide 398121 by 12
We want to divide 398121 by 12.

Moving on to step 1:
If we divide 3 by 12, we get 0 and a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 3, we get 3.
Fetch the next digit (9) from the dividend, attach it to 3 and continue: 39 / 12

Let's proceed to step 2:
12 goes into 39 3 times with a remainder of 3.
The next digit of our result is 3. 
Result so far: 3.0
If we take 36 away from 39, we end up with 3.
Take the next digit (8) from the dividend and append it to 3, then repeat: 38 / 12

Going ahead to step 3:
The number 12 fits into 38 3 times, leaving a remainder of 2.
Record the quotient 3 as the next digit in the result. 
Result so far: 33.0
The remainder is 2 after subtracting 36 from 38.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 12

On to step 4:
The number 12 fits into 21 1 times, leaving a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 331.0
The remainder is 9 after subtracting 12 from 21.
Take the next digit (2) from the dividend and append it to 9, then repeat: 92 / 12

On to step 5:
When dividing 92 by 12, we get 7 with a remainder of 8.
Record the quotient 7 as the next digit in the result. 
Result so far: 3317.0
Subtracting 84 from 92 leaves us with 8.
Append the next digit (1) from the dividend to 8 and continue with: 81 / 12

Step 6:
When dividing 81 by 12, we get 6 with a remainder of 9.
Use 6 as the next digit of our solution. 
Result so far: 33176.0
Subtracting 72 from 81 leaves us with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 7:
If we divide 90 by 12, we get 7 and a remainder of 6.
The next digit of our result is 7. 
Result so far: 33176.7
The remainder is 6 after subtracting 84 from 90.
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 goes into 60 5 times with a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 33176.75
The remainder is 0 after subtracting 60 from 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 9:
The number 12 fits into 0 0 times, leaving a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 33176.75
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 10:
0 divided by 12 is 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 33176.75
Deduct 0 from 0 and we're left 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.

After the division, we end up with 33176.75 and a remainder of 0.0.