We're dividing 490182 by 21 
Let's see how many times 21 fits into 490182.

Step 1:
21 goes into 4 0 times with a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Fetch the next digit (9) from the dividend, attach it to 4 and continue: 49 / 21

Advancing to step 2:
21 can be fit into 49 2 times, resulting in a remainder of 7.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtracting 42 from 49 leaves us with 7.
Take the next digit (0) from the dividend and append it to 7, then repeat: 70 / 21

Moving on to step 3:
21 goes into 70 3 times with a remainder of 7.
Record the quotient 3 as the next digit in the result. 
Result so far: 23.0
The remainder is 7 after subtracting 63 from 70.
Take the next digit (1) from the dividend and append it to 7, then repeat: 71 / 21

Step 4:
The number 21 fits into 71 3 times, leaving a remainder of 8.
Write down 3 as next digit of the result. 
Result so far: 233.0
If we subtract 63 from 71, we get 8.
Bring next digit (8) of the dividend behind the 8 and repeat the process: 88 / 21

On to step 5:
21 goes into 88 4 times with a remainder of 4.
Record the quotient 4 as the next digit in the result. 
Result so far: 2334.0
The remainder is 4 after subtracting 84 from 88.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 21

Let's proceed to step 6:
If we divide 42 by 21, we get 2 and a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 23342.0
Subtracting 42 from 42 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 7:
If we divide 0 by 21, we get 0 and a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 23342.0
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 8:
21 can be fit into 0 0 times, resulting in a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 23342.0
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 23342.0 with a remainder of 0.0.