We're dividing 80509391 by 51 
We want to figure out the number of times 80509391 can be divided by 51.

Going ahead to step 1:
8 divided by 51 is 0 with 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

Going ahead to step 2:
The number 51 fits into 80 1 times, leaving a remainder of 29.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtract 51 from 80 to get 29.
Fetch the next digit (5) from the dividend, attach it to 29 and continue: 295 / 51

Step 3:
When dividing 295 by 51, we get 5 with a remainder of 40.
The next digit of our result is 5. 
Result so far: 15.0
The remainder is 40 after subtracting 255 from 295.
Take the next digit (0) from the dividend and append it to 40, then repeat: 400 / 51

Advancing to step 4:
The number 51 fits into 400 7 times, leaving a remainder of 43.
Use 7 as the next digit of our solution. 
Result so far: 157.0
The remainder is 43 after subtracting 357 from 400.
Include the next digit (9) from the dividend after 43, then repeat: 439 / 51

On to step 5:
51 can be fit into 439 8 times, resulting in a remainder of 31.
Record the quotient 8 as the next digit in the result. 
Result so far: 1578.0
The remainder is 31 after subtracting 408 from 439.
Fetch the next digit (3) from the dividend, attach it to 31 and continue: 313 / 51

Let's proceed to step 6:
51 goes into 313 6 times with a remainder of 7.
Use 6 as the next digit of our solution. 
Result so far: 15786.0
Subtracting 306 from 313 leaves us with 7.
Take the next digit (9) from the dividend and append it to 7, then repeat: 79 / 51

Step 7:
When dividing 79 by 51, we get 1 with a remainder of 28.
Record the quotient 1 as the next digit in the result. 
Result so far: 157861.0
Subtract 51 from 79 to get 28.
Append the next digit (1) from the dividend to 28 and continue with: 281 / 51

Moving on to step 8:
If we divide 281 by 51, we get 5 and a remainder of 26.
Use 5 as the next digit of our solution. 
Result so far: 1578615.0
Deduct 255 from 281 and we're left with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Let's proceed to step 9:
When dividing 260 by 51, we get 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 1578615.5
Subtracting 255 from 260 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 10:
If we divide 50 by 51, we get 0 and a remainder of 50.
Write down 0 as next digit of the result. 
Result so far: 1578615.5
If we take 0 away from 50, we end up 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.

Going ahead to step 11:
The number 51 fits into 500 9 times, leaving a remainder of 41.
Put 9 as the next digit of the answer. 
Result so far: 1578615.509
The remainder is 41 after subtracting 459 from 500.
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:
When dividing 410 by 51, we get 8 with a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 1578615.5098
The remainder is 2 after subtracting 408 from 410.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 13:
20 divided by 51 is 0 with a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 1578615.5098
Subtracting 0 from 20 leaves us 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.

Let's proceed to step 14:
200 divided by 51 is 3 with a remainder of 47.
Use 3 as the next digit of our solution. 
Result so far: 1578615.509803
Deduct 153 from 200 and we're left 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.

Going ahead to step 15:
51 can be fit into 470 9 times, resulting in a remainder of 11.
The next digit of our result is 9. 
Result so far: 1578615.5098039
If we subtract 459 from 470, 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.

Going ahead to step 16:
51 goes into 110 2 times with a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 1578615.50980392
Subtract 102 from 110 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

The quotient of the division is 1578615.50980392, and the remainder is 8e-09.