We look at the division of 166921 by 12 
Our goal is to divide 166921 by 12.

Step 1:
If we divide 1 by 12, we get 0 and a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Include the next digit (6) from the dividend after 1, then repeat: 16 / 12

On to step 2:
16 divided by 12 is 1 with a remainder of 4.
The next digit of our result is 1. 
Result so far: 1.0
The remainder is 4 after subtracting 12 from 16.
Fetch the next digit (6) from the dividend, attach it to 4 and continue: 46 / 12

Moving on to step 3:
If we divide 46 by 12, we get 3 and a remainder of 10.
Record the quotient 3 as the next digit in the result. 
Result so far: 13.0
If we take 36 away from 46, we end up with 10.
Fetch the next digit (9) from the dividend, attach it to 10 and continue: 109 / 12

Advancing to step 4:
109 divided by 12 is 9 with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 139.0
Deduct 108 from 109 and we're left with 1.
Include the next digit (2) from the dividend after 1, then repeat: 12 / 12

Let's proceed to step 5:
12 divided by 12 is 1 with a remainder of 0.
Write down 1 as next digit of the result. 
Result so far: 1391.0
Deduct 12 from 12 and we're left with 0.
Include the next digit (1) from the dividend after 0, then repeat: 1 / 12

On to step 6:
1 divided by 12 is 0 with a remainder of 1.
The next digit of our result is 0. 
Result so far: 13910.0
Deduct 0 from 1 and we're left 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.

On to step 7:
If we divide 10 by 12, we get 0 and a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 13910.0
Subtracting 0 from 10 leaves us 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.

Moving on to step 8:
When dividing 100 by 12, we get 8 with a remainder of 4.
Put 8 as the next digit of the answer. 
Result so far: 13910.08
The remainder is 4 after subtracting 96 from 100.
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:
12 goes into 40 3 times with a remainder of 4.
Put 3 as the next digit of the answer. 
Result so far: 13910.083
Deduct 36 from 40 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.

Moving on to step 10:
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: 13910.0833
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.

Our division results in 13910.0833 with a remaining 4e-05.