We look at the division of 768486 by 51 
We're looking to find how many times 51 goes into 768486.

On to step 1:
The number 51 fits into 7 0 times, leaving a remainder of 7.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 7 after subtracting 0 from 7.
Bring next digit (6) of the dividend behind the 7 and repeat the process: 76 / 51

Advancing to step 2:
51 goes into 76 1 times with a remainder of 25.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we subtract 51 from 76, we get 25.
Include the next digit (8) from the dividend after 25, then repeat: 258 / 51

On to step 3:
If we divide 258 by 51, we get 5 and a remainder of 3.
Write down 5 as next digit of the result. 
Result so far: 15.0
If we subtract 255 from 258, we get 3.
Grab the next digit (4) from the dividend, add it to 3, then carry on: 34 / 51

Step 4:
If we divide 34 by 51, we get 0 and a remainder of 34.
Use 0 as the next digit of our solution. 
Result so far: 150.0
If we subtract 0 from 34, we get 34.
Append the next digit (8) from the dividend to 34 and continue with: 348 / 51

On to step 5:
51 can be fit into 348 6 times, resulting in a remainder of 42.
Write down 6 as next digit of the result. 
Result so far: 1506.0
Subtracting 306 from 348 leaves us with 42.
Include the next digit (6) from the dividend after 42, then repeat: 426 / 51

Moving on to step 6:
The number 51 fits into 426 8 times, leaving a remainder of 18.
The number 8 becomes the next digit in our result. 
Result so far: 15068.0
Deduct 408 from 426 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

On to step 7:
51 can be fit into 180 3 times, resulting in a remainder of 27.
Use 3 as the next digit of our solution. 
Result so far: 15068.3
The remainder is 27 after subtracting 153 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 270, and continue the process.

Let's proceed to step 8:
51 can be fit into 270 5 times, resulting in a remainder of 15.
Put 5 as the next digit of the answer. 
Result so far: 15068.35
If we take 255 away from 270, we end up with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 9:
51 can be fit into 150 2 times, resulting in a remainder of 48.
Use 2 as the next digit of our solution. 
Result so far: 15068.352
If we subtract 102 from 150, we get 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Moving on to step 10:
51 goes into 480 9 times with a remainder of 21.
Record the quotient 9 as the next digit in the result. 
Result so far: 15068.3529
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 11:
If we divide 210 by 51, we get 4 and a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 15068.35294
The remainder is 6 after subtracting 204 from 210.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 12:
60 divided by 51 is 1 with a remainder of 9.
The next digit of our result is 1. 
Result so far: 15068.352941
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.

Going ahead to step 13:
90 divided by 51 is 1 with a remainder of 39.
Write down 1 as next digit of the result. 
Result so far: 15068.3529411
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.

After the division, we end up with 15068.3529411 and a remainder of 3.9e-07.