We're dividing 843568 by 21 
Our goal is to divide 843568 by 21.

Step 1:
The number 21 fits into 8 0 times, leaving a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Grab the next digit (4) from the dividend, add it to 8, then carry on: 84 / 21

On to step 2:
21 can be fit into 84 4 times, resulting in a remainder of 0.
Use 4 as the next digit of our solution. 
Result so far: 4.0
Subtracting 84 from 84 leaves us with 0.
Bring next digit (3) of the dividend behind the 0 and repeat the process: 3 / 21

Advancing to step 3:
21 goes into 3 0 times with a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 40.0
If we take 0 away from 3, we end up with 3.
Bring next digit (5) of the dividend behind the 3 and repeat the process: 35 / 21

Let's proceed to step 4:
21 can be fit into 35 1 times, resulting in a remainder of 14.
Use 1 as the next digit of our solution. 
Result so far: 401.0
If we take 21 away from 35, we end up with 14.
Fetch the next digit (6) from the dividend, attach it to 14 and continue: 146 / 21

Let's proceed to step 5:
The number 21 fits into 146 6 times, leaving a remainder of 20.
The number 6 becomes the next digit in our result. 
Result so far: 4016.0
Deduct 126 from 146 and we're left with 20.
Grab the next digit (8) from the dividend, add it to 20, then carry on: 208 / 21

On to step 6:
21 goes into 208 9 times with a remainder of 19.
The number 9 becomes the next digit in our result. 
Result so far: 40169.0
If we subtract 189 from 208, we get 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Moving on to step 7:
If we divide 190 by 21, we get 9 and a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 40169.9
If we take 189 away from 190, 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.

On to step 8:
10 divided by 21 is 0 with a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 40169.9
Deduct 0 from 10 and we're left 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.

Advancing to step 9:
21 can be fit into 100 4 times, resulting in a remainder of 16.
The next digit of our result is 4. 
Result so far: 40169.904
Deduct 84 from 100 and we're left with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Step 10:
21 can be fit into 160 7 times, resulting in a remainder of 13.
Write down 7 as next digit of the result. 
Result so far: 40169.9047
If we take 147 away from 160, we end up with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Advancing to step 11:
When dividing 130 by 21, we get 6 with a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 40169.90476
If we subtract 126 from 130, 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 12:
When dividing 40 by 21, we get 1 with a remainder of 19.
The next digit of our result is 1. 
Result so far: 40169.904761
If we take 21 away from 40, we end up with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Moving on to step 13:
21 goes into 190 9 times with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 40169.9047619
The remainder is 1 after subtracting 189 from 190.
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 14:
10 divided by 21 is 0 with a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 40169.9047619
Subtract 0 from 10 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

After the division, we end up with 40169.9047619 and a remainder of 1e-08.