We look at the division of 808439 by 51 
We want to figure out the number of times 808439 can be divided by 51.

On to step 1:
51 can be fit into 8 0 times, resulting in a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Take the next digit (0) from the dividend and append it to 8, then repeat: 80 / 51

Advancing to step 2:
51 can be fit into 80 1 times, resulting in a remainder of 29.
Use 1 as the next digit of our solution. 
Result so far: 1.0
If we take 51 away from 80, we end up with 29.
Bring next digit (8) of the dividend behind the 29 and repeat the process: 298 / 51

Step 3:
If we divide 298 by 51, we get 5 and a remainder of 43.
Write down 5 as next digit of the result. 
Result so far: 15.0
Subtracting 255 from 298 leaves us with 43.
Grab the next digit (4) from the dividend, add it to 43, then carry on: 434 / 51

Step 4:
51 can be fit into 434 8 times, resulting in a remainder of 26.
The next digit of our result is 8. 
Result so far: 158.0
Subtract 408 from 434 to get 26.
Include the next digit (3) from the dividend after 26, then repeat: 263 / 51

On to step 5:
If we divide 263 by 51, we get 5 and a remainder of 8.
The number 5 becomes the next digit in our result. 
Result so far: 1585.0
Subtracting 255 from 263 leaves us with 8.
Take the next digit (9) from the dividend and append it to 8, then repeat: 89 / 51

On to step 6:
If we divide 89 by 51, we get 1 and a remainder of 38.
The number 1 becomes the next digit in our result. 
Result so far: 15851.0
Subtract 51 from 89 to get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Step 7:
380 divided by 51 is 7 with a remainder of 23.
Use 7 as the next digit of our solution. 
Result so far: 15851.7
If we take 357 away from 380, we end up with 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Going ahead to step 8:
The number 51 fits into 230 4 times, leaving a remainder of 26.
Write down 4 as next digit of the result. 
Result so far: 15851.74
If we subtract 204 from 230, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Moving on to step 9:
260 divided by 51 is 5 with a remainder of 5.
The number 5 becomes the next digit in our result. 
Result so far: 15851.745
Subtract 255 from 260 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.

Moving on to step 10:
When dividing 50 by 51, we get 0 with a remainder of 50.
Write down 0 as next digit of the result. 
Result so far: 15851.745
Deduct 0 from 50 and we're left with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Step 11:
51 can be fit into 500 9 times, resulting in a remainder of 41.
Put 9 as the next digit of the answer. 
Result so far: 15851.74509
Subtracting 459 from 500 leaves us with 41.
Since there are no more digits in the dividend, we add a zero to the remainder making it 410, and continue the process.

Going ahead to step 12:
The number 51 fits into 410 8 times, leaving a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 15851.745098
If we take 408 away from 410, we end up 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.

Advancing to step 13:
If we divide 20 by 51, we get 0 and a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 15851.745098
Deduct 0 from 20 and we're left 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 14:
The number 51 fits into 200 3 times, leaving a remainder of 47.
The next digit of our result is 3. 
Result so far: 15851.74509803
Subtracting 153 from 200 leaves us with 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

The quotient of the division is 15851.74509803, and the remainder is 4.7e-08.