102872 ÷ 51 
We're looking to find how many times 51 goes into 102872.

Step 1:
The number 51 fits into 1 0 times, leaving a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 51

On to step 2:
If we divide 10 by 51, we get 0 and a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 10 after subtracting 0 from 10.
Include the next digit (2) from the dividend after 10, then repeat: 102 / 51

Let's proceed to step 3:
The number 51 fits into 102 2 times, leaving a remainder of 0.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
The remainder is 0 after subtracting 102 from 102.
Append the next digit (8) from the dividend to 0 and continue with: 8 / 51

Going ahead to step 4:
51 goes into 8 0 times with a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 20.0
The remainder is 8 after subtracting 0 from 8.
Take the next digit (7) from the dividend and append it to 8, then repeat: 87 / 51

Moving on to step 5:
The number 51 fits into 87 1 times, leaving a remainder of 36.
Write down 1 as next digit of the result. 
Result so far: 201.0
Deduct 51 from 87 and we're left with 36.
Grab the next digit (2) from the dividend, add it to 36, then carry on: 362 / 51

On to step 6:
If we divide 362 by 51, we get 7 and a remainder of 5.
Use 7 as the next digit of our solution. 
Result so far: 2017.0
The remainder is 5 after subtracting 357 from 362.
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 7:
When dividing 50 by 51, we get 0 with a remainder of 50.
Put 0 as the next digit of the answer. 
Result so far: 2017.0
Subtracting 0 from 50 leaves us 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.

On to step 8:
51 can be fit into 500 9 times, resulting in a remainder of 41.
Use 9 as the next digit of our solution. 
Result so far: 2017.09
If we take 459 away from 500, we end up 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.

Advancing to step 9:
If we divide 410 by 51, we get 8 and a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 2017.098
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.

Step 10:
51 goes into 20 0 times with a remainder of 20.
The next digit of our result is 0. 
Result so far: 2017.098
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.

Step 11:
When dividing 200 by 51, we get 3 with a remainder of 47.
Put 3 as the next digit of the answer. 
Result so far: 2017.09803
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.

Let's proceed to step 12:
If we divide 470 by 51, we get 9 and a remainder of 11.
The next digit of our result is 9. 
Result so far: 2017.098039
The remainder is 11 after subtracting 459 from 470.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Step 13:
110 divided by 51 is 2 with a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 2017.0980392
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.

On to step 14:
If we divide 80 by 51, we get 1 and a remainder of 29.
The next digit of our result is 1. 
Result so far: 2017.09803921
If we take 51 away from 80, we end up with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

After the division, we end up with 2017.09803921 and a remainder of 2.9e-08.