We're dividing 431678 by 21 
We want to figure out the number of times 431678 can be divided by 21.

Let's proceed to step 1:
If we divide 4 by 21, we get 0 and a remainder of 4.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Append the next digit (3) from the dividend to 4 and continue with: 43 / 21

Moving on to step 2:
When dividing 43 by 21, we get 2 with a remainder of 1.
The next digit of our result is 2. 
Result so far: 2.0
Subtracting 42 from 43 leaves us with 1.
Bring next digit (1) of the dividend behind the 1 and repeat the process: 11 / 21

Going ahead to step 3:
When dividing 11 by 21, we get 0 with a remainder of 11.
Record the quotient 0 as the next digit in the result. 
Result so far: 20.0
If we subtract 0 from 11, we get 11.
Fetch the next digit (6) from the dividend, attach it to 11 and continue: 116 / 21

Step 4:
116 divided by 21 is 5 with a remainder of 11.
The number 5 becomes the next digit in our result. 
Result so far: 205.0
If we take 105 away from 116, we end up with 11.
Append the next digit (7) from the dividend to 11 and continue with: 117 / 21

Let's proceed to step 5:
21 goes into 117 5 times with a remainder of 12.
Put 5 as the next digit of the answer. 
Result so far: 2055.0
If we take 105 away from 117, we end up with 12.
Grab the next digit (8) from the dividend, add it to 12, then carry on: 128 / 21

Going ahead to step 6:
The number 21 fits into 128 6 times, leaving a remainder of 2.
The number 6 becomes the next digit in our result. 
Result so far: 20556.0
Deduct 126 from 128 and we're left 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.

On to step 7:
If we divide 20 by 21, we get 0 and a remainder of 20.
The next digit of our result is 0. 
Result so far: 20556.0
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.

Let's proceed to step 8:
When dividing 200 by 21, we get 9 with a remainder of 11.
The next digit of our result is 9. 
Result so far: 20556.09
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.

Advancing to step 9:
110 divided by 21 is 5 with a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 20556.095
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:
If we divide 50 by 21, we get 2 and a remainder of 8.
The next digit of our result is 2. 
Result so far: 20556.0952
Subtract 42 from 50 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 11:
21 can be fit into 80 3 times, resulting in a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 20556.09523
If we take 63 away from 80, we end up 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.

Going ahead to step 12:
If we divide 170 by 21, we get 8 and a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 20556.095238
The remainder is 2 after subtracting 168 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 13:
20 divided by 21 is 0 with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 20556.095238
Subtracting 0 from 20 leaves us 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.

Let's proceed to step 14:
21 goes into 200 9 times with a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 20556.09523809
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.

After the division, we end up with 20556.09523809 and a remainder of 1.1e-08.