We look at the division of 429900 by 51 
We want to divide 429900 by 51.

Let's proceed to step 1:
The number 51 fits into 4 0 times, leaving a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Append the next digit (2) from the dividend to 4 and continue with: 42 / 51

Going ahead to step 2:
When dividing 42 by 51, we get 0 with a remainder of 42.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 42, we end up with 42.
Fetch the next digit (9) from the dividend, attach it to 42 and continue: 429 / 51

Moving on to step 3:
The number 51 fits into 429 8 times, leaving a remainder of 21.
The next digit of our result is 8. 
Result so far: 8.0
The remainder is 21 after subtracting 408 from 429.
Bring next digit (9) of the dividend behind the 21 and repeat the process: 219 / 51

Let's proceed to step 4:
The number 51 fits into 219 4 times, leaving a remainder of 15.
Put 4 as the next digit of the answer. 
Result so far: 84.0
The remainder is 15 after subtracting 204 from 219.
Append the next digit (0) from the dividend to 15 and continue with: 150 / 51

Let's proceed to step 5:
The number 51 fits into 150 2 times, leaving a remainder of 48.
The number 2 becomes the next digit in our result. 
Result so far: 842.0
Subtracting 102 from 150 leaves us with 48.
Bring next digit (0) of the dividend behind the 48 and repeat the process: 480 / 51

On to step 6:
If we divide 480 by 51, we get 9 and a remainder of 21.
The number 9 becomes the next digit in our result. 
Result so far: 8429.0
If we take 459 away from 480, we end up with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Step 7:
The number 51 fits into 210 4 times, leaving a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 8429.4
Subtracting 204 from 210 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Let's proceed to step 8:
51 can be fit into 60 1 times, resulting in a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 8429.41
If we take 51 away from 60, we end up with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 9:
If we divide 90 by 51, we get 1 and a remainder of 39.
Use 1 as the next digit of our solution. 
Result so far: 8429.411
Deduct 51 from 90 and we're left with 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

The quotient of the division is 8429.411, and the remainder is 0.0039.