Let's divide 9459429 by 21
We want to divide 9459429 by 21.

Advancing to step 1:
When dividing 9 by 21, we get 0 with a remainder of 9.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 9 to get 9.
Bring next digit (4) of the dividend behind the 9 and repeat the process: 94 / 21

Step 2:
21 goes into 94 4 times with a remainder of 10.
The next digit of our result is 4. 
Result so far: 4.0
If we subtract 84 from 94, we get 10.
Bring next digit (5) of the dividend behind the 10 and repeat the process: 105 / 21

Moving on to step 3:
The number 21 fits into 105 5 times, leaving a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 45.0
Deduct 105 from 105 and we're left with 0.
Take the next digit (9) from the dividend and append it to 0, then repeat: 9 / 21

Step 4:
When dividing 9 by 21, we get 0 with a remainder of 9.
Write down 0 as next digit of the result. 
Result so far: 450.0
Subtract 0 from 9 to get 9.
Grab the next digit (4) from the dividend, add it to 9, then carry on: 94 / 21

Moving on to step 5:
When dividing 94 by 21, we get 4 with a remainder of 10.
Write down 4 as next digit of the result. 
Result so far: 4504.0
Deduct 84 from 94 and we're left with 10.
Append the next digit (2) from the dividend to 10 and continue with: 102 / 21

Moving on to step 6:
The number 21 fits into 102 4 times, leaving a remainder of 18.
The number 4 becomes the next digit in our result. 
Result so far: 45044.0
Deduct 84 from 102 and we're left with 18.
Bring next digit (9) of the dividend behind the 18 and repeat the process: 189 / 21

Going ahead to step 7:
21 goes into 189 9 times with a remainder of 0.
Write down 9 as next digit of the result. 
Result so far: 450449.0
If we subtract 189 from 189, 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.

Advancing to step 8:
If we divide 0 by 21, we get 0 and a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 450449.0
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.

Advancing to step 9:
21 can be fit into 0 0 times, resulting in a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 450449.0
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.

After the division, we end up with 450449.0 and a remainder of 0.0.