Let's divide 666668 by 21
Let's see how many times 21 fits into 666668.

Moving on to step 1:
21 can be fit into 6 0 times, resulting in a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Append the next digit (6) from the dividend to 6 and continue with: 66 / 21

Going ahead to step 2:
The number 21 fits into 66 3 times, leaving a remainder of 3.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
If we take 63 away from 66, we end up with 3.
Bring next digit (6) of the dividend behind the 3 and repeat the process: 36 / 21

Let's proceed to step 3:
21 goes into 36 1 times with a remainder of 15.
Write down 1 as next digit of the result. 
Result so far: 31.0
Deduct 21 from 36 and we're left with 15.
Include the next digit (6) from the dividend after 15, then repeat: 156 / 21

Let's proceed to step 4:
When dividing 156 by 21, we get 7 with a remainder of 9.
Use 7 as the next digit of our solution. 
Result so far: 317.0
Subtract 147 from 156 to get 9.
Take the next digit (6) from the dividend and append it to 9, then repeat: 96 / 21

Moving on to step 5:
The number 21 fits into 96 4 times, leaving a remainder of 12.
The number 4 becomes the next digit in our result. 
Result so far: 3174.0
Subtract 84 from 96 to get 12.
Append the next digit (8) from the dividend to 12 and continue with: 128 / 21

Let's proceed to step 6:
The number 21 fits into 128 6 times, leaving a remainder of 2.
Write down 6 as next digit of the result. 
Result so far: 31746.0
Subtracting 126 from 128 leaves us with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 7:
21 can be fit into 20 0 times, resulting in a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 31746.0
If we subtract 0 from 20, we get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 8:
21 can be fit into 200 9 times, resulting in a remainder of 11.
Put 9 as the next digit of the answer. 
Result so far: 31746.09
Subtract 189 from 200 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

On to step 9:
When dividing 110 by 21, we get 5 with a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 31746.095
Subtracting 105 from 110 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 10:
The number 21 fits into 50 2 times, leaving a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 31746.0952
The remainder is 8 after subtracting 42 from 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

On to step 11:
When dividing 80 by 21, we get 3 with a remainder of 17.
Put 3 as the next digit of the answer. 
Result so far: 31746.09523
Deduct 63 from 80 and we're left with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Advancing to step 12:
21 can be fit into 170 8 times, resulting in a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 31746.095238
If we subtract 168 from 170, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Advancing to step 13:
If we divide 20 by 21, we get 0 and a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 31746.095238
If we take 0 away from 20, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Step 14:
When dividing 200 by 21, we get 9 with a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 31746.09523809
Deduct 189 from 200 and we're left with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

The final outcome is 31746.09523809, with a leftover of 1.1e-08.