429992 ÷ 21 
We want to divide 429992 by 21.

Going ahead to step 1:
21 goes into 4 0 times with a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 4 leaves us with 4.
Append the next digit (2) from the dividend to 4 and continue with: 42 / 21

Step 2:
21 goes into 42 2 times with a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Subtract 42 from 42 to get 0.
Include the next digit (9) from the dividend after 0, then repeat: 9 / 21

Moving on to step 3:
9 divided by 21 is 0 with a remainder of 9.
Write down 0 as next digit of the result. 
Result so far: 20.0
Deduct 0 from 9 and we're left with 9.
Append the next digit (9) from the dividend to 9 and continue with: 99 / 21

Step 4:
99 divided by 21 is 4 with a remainder of 15.
Use 4 as the next digit of our solution. 
Result so far: 204.0
Subtract 84 from 99 to get 15.
Include the next digit (9) from the dividend after 15, then repeat: 159 / 21

On to step 5:
If we divide 159 by 21, we get 7 and a remainder of 12.
Record the quotient 7 as the next digit in the result. 
Result so far: 2047.0
The remainder is 12 after subtracting 147 from 159.
Grab the next digit (2) from the dividend, add it to 12, then carry on: 122 / 21

Going ahead to step 6:
122 divided by 21 is 5 with a remainder of 17.
The next digit of our result is 5. 
Result so far: 20475.0
Subtracting 105 from 122 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 7:
21 goes into 170 8 times with a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 20475.8
Deduct 168 from 170 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.

Let's proceed to step 8:
The number 21 fits into 20 0 times, leaving a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 20475.8
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.

Step 9:
The number 21 fits into 200 9 times, leaving a remainder of 11.
The next digit of our result is 9. 
Result so far: 20475.809
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.

On to step 10:
21 can be fit into 110 5 times, resulting in a remainder of 5.
The next digit of our result is 5. 
Result so far: 20475.8095
Subtract 105 from 110 to 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.

Going ahead to step 11:
When dividing 50 by 21, we get 2 with a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 20475.80952
If we take 42 away from 50, we end up 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.

Advancing to step 12:
80 divided by 21 is 3 with a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 20475.809523
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.

On to step 13:
170 divided by 21 is 8 with a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 20475.8095238
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 14:
20 divided by 21 is 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 20475.8095238
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.

After the division, we end up with 20475.8095238 and a remainder of 2e-08.