We're dividing 789721 by 51 
The aim is to understand the frequency of 51 in 789721.

Moving on to step 1:
7 divided by 51 is 0 with a remainder of 7.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Grab the next digit (8) from the dividend, add it to 7, then carry on: 78 / 51

Let's proceed to step 2:
51 goes into 78 1 times with a remainder of 27.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
If we take 51 away from 78, we end up with 27.
Grab the next digit (9) from the dividend, add it to 27, then carry on: 279 / 51

On to step 3:
279 divided by 51 is 5 with a remainder of 24.
Write down 5 as next digit of the result. 
Result so far: 15.0
Deduct 255 from 279 and we're left with 24.
Bring next digit (7) of the dividend behind the 24 and repeat the process: 247 / 51

Let's proceed to step 4:
51 can be fit into 247 4 times, resulting in a remainder of 43.
Put 4 as the next digit of the answer. 
Result so far: 154.0
The remainder is 43 after subtracting 204 from 247.
Include the next digit (2) from the dividend after 43, then repeat: 432 / 51

Going ahead to step 5:
51 goes into 432 8 times with a remainder of 24.
Put 8 as the next digit of the answer. 
Result so far: 1548.0
Subtract 408 from 432 to get 24.
Grab the next digit (1) from the dividend, add it to 24, then carry on: 241 / 51

Step 6:
51 can be fit into 241 4 times, resulting in a remainder of 37.
Put 4 as the next digit of the answer. 
Result so far: 15484.0
If we subtract 204 from 241, we get 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Going ahead to step 7:
If we divide 370 by 51, we get 7 and a remainder of 13.
The next digit of our result is 7. 
Result so far: 15484.7
If we take 357 away from 370, we end up with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

On to step 8:
The number 51 fits into 130 2 times, leaving a remainder of 28.
Write down 2 as next digit of the result. 
Result so far: 15484.72
Subtract 102 from 130 to get 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

On to step 9:
51 can be fit into 280 5 times, resulting in a remainder of 25.
Write down 5 as next digit of the result. 
Result so far: 15484.725
If we subtract 255 from 280, we get 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Going ahead to step 10:
51 can be fit into 250 4 times, resulting in a remainder of 46.
Record the quotient 4 as the next digit in the result. 
Result so far: 15484.7254
Subtract 204 from 250 to get 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 460, and continue the process.

On to step 11:
When dividing 460 by 51, we get 9 with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 15484.72549
Subtracting 459 from 460 leaves us with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 12:
51 goes into 10 0 times with a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 15484.72549
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Step 13:
100 divided by 51 is 1 with a remainder of 49.
The next digit of our result is 1. 
Result so far: 15484.7254901
Subtract 51 from 100 to get 49.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

Moving on to step 14:
The number 51 fits into 490 9 times, leaving a remainder of 31.
The number 9 becomes the next digit in our result. 
Result so far: 15484.72549019
The remainder is 31 after subtracting 459 from 490.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

The final outcome is 15484.72549019, with a leftover of 3.1e-08.