We divide 648443 by 21
We want to divide 648443 by 21.

Step 1:
If we divide 6 by 21, we get 0 and a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 6, we get 6.
Fetch the next digit (4) from the dividend, attach it to 6 and continue: 64 / 21

Advancing to step 2:
21 goes into 64 3 times with a remainder of 1.
Write down 3 as next digit of the result. 
Result so far: 3.0
If we take 63 away from 64, we end up with 1.
Fetch the next digit (8) from the dividend, attach it to 1 and continue: 18 / 21

Moving on to step 3:
If we divide 18 by 21, we get 0 and a remainder of 18.
Put 0 as the next digit of the answer. 
Result so far: 30.0
If we subtract 0 from 18, we get 18.
Bring next digit (4) of the dividend behind the 18 and repeat the process: 184 / 21

Let's proceed to step 4:
When dividing 184 by 21, we get 8 with a remainder of 16.
Put 8 as the next digit of the answer. 
Result so far: 308.0
Deduct 168 from 184 and we're left with 16.
Bring next digit (4) of the dividend behind the 16 and repeat the process: 164 / 21

Step 5:
The number 21 fits into 164 7 times, leaving a remainder of 17.
Use 7 as the next digit of our solution. 
Result so far: 3087.0
Deduct 147 from 164 and we're left with 17.
Grab the next digit (3) from the dividend, add it to 17, then carry on: 173 / 21

Going ahead to step 6:
The number 21 fits into 173 8 times, leaving a remainder of 5.
Record the quotient 8 as the next digit in the result. 
Result so far: 30878.0
If we subtract 168 from 173, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 7:
21 can be fit into 50 2 times, resulting in a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 30878.2
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.

Let's proceed to step 8:
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: 30878.23
Subtracting 63 from 80 leaves us 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.

Let's proceed to step 9:
When dividing 170 by 21, we get 8 with a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 30878.238
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.

Moving on to step 10:
21 goes into 20 0 times with a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 30878.238
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.

Advancing to step 11:
The number 21 fits into 200 9 times, leaving a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 30878.23809
If we subtract 189 from 200, we 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 12:
21 goes into 110 5 times with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 30878.238095
If we take 105 away from 110, we end up 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 13:
21 goes into 50 2 times with a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 30878.2380952
Subtracting 42 from 50 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 14:
When dividing 80 by 21, we get 3 with a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 30878.23809523
The remainder is 17 after subtracting 63 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

After the division, we end up with 30878.23809523 and a remainder of 1.7e-08.