We're dividing 991878 by 51 
We want to figure out the number of times 991878 can be divided by 51.

Moving on to step 1:
51 goes into 9 0 times with a remainder of 9.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 9 to get 9.
Take the next digit (9) from the dividend and append it to 9, then repeat: 99 / 51

Moving on to step 2:
99 divided by 51 is 1 with a remainder of 48.
Use 1 as the next digit of our solution. 
Result so far: 1.0
The remainder is 48 after subtracting 51 from 99.
Bring next digit (1) of the dividend behind the 48 and repeat the process: 481 / 51

Moving on to step 3:
51 goes into 481 9 times with a remainder of 22.
The next digit of our result is 9. 
Result so far: 19.0
Deduct 459 from 481 and we're left with 22.
Include the next digit (8) from the dividend after 22, then repeat: 228 / 51

Going ahead to step 4:
If we divide 228 by 51, we get 4 and a remainder of 24.
Record the quotient 4 as the next digit in the result. 
Result so far: 194.0
Subtract 204 from 228 to get 24.
Fetch the next digit (7) from the dividend, attach it to 24 and continue: 247 / 51

Moving on to step 5:
The number 51 fits into 247 4 times, leaving a remainder of 43.
The number 4 becomes the next digit in our result. 
Result so far: 1944.0
If we subtract 204 from 247, we get 43.
Take the next digit (8) from the dividend and append it to 43, then repeat: 438 / 51

Let's proceed to step 6:
The number 51 fits into 438 8 times, leaving a remainder of 30.
Write down 8 as next digit of the result. 
Result so far: 19448.0
Deduct 408 from 438 and we're left with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Let's proceed to step 7:
300 divided by 51 is 5 with a remainder of 45.
Put 5 as the next digit of the answer. 
Result so far: 19448.5
The remainder is 45 after subtracting 255 from 300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Going ahead to step 8:
When dividing 450 by 51, we get 8 with a remainder of 42.
Write down 8 as next digit of the result. 
Result so far: 19448.58
Subtract 408 from 450 to get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Moving on to step 9:
The number 51 fits into 420 8 times, leaving a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 19448.588
If we take 408 away from 420, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

The final outcome is 19448.588, with a leftover of 0.0012.