Let's divide 129512 by 77
The aim is to understand the frequency of 77 in 129512.

On to step 1:
If we divide 1 by 77, we get 0 and a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Fetch the next digit (2) from the dividend, attach it to 1 and continue: 12 / 77

On to step 2:
77 can be fit into 12 0 times, resulting in a remainder of 12.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 12 to get 12.
Bring next digit (9) of the dividend behind the 12 and repeat the process: 129 / 77

Let's proceed to step 3:
77 goes into 129 1 times with a remainder of 52.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Deduct 77 from 129 and we're left with 52.
Grab the next digit (5) from the dividend, add it to 52, then carry on: 525 / 77

On to step 4:
The number 77 fits into 525 6 times, leaving a remainder of 63.
The next digit of our result is 6. 
Result so far: 16.0
Deduct 462 from 525 and we're left with 63.
Include the next digit (1) from the dividend after 63, then repeat: 631 / 77

On to step 5:
When dividing 631 by 77, we get 8 with a remainder of 15.
Write down 8 as next digit of the result. 
Result so far: 168.0
The remainder is 15 after subtracting 616 from 631.
Fetch the next digit (2) from the dividend, attach it to 15 and continue: 152 / 77

Advancing to step 6:
77 can be fit into 152 1 times, resulting in a remainder of 75.
Record the quotient 1 as the next digit in the result. 
Result so far: 1681.0
Subtracting 77 from 152 leaves us with 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Going ahead to step 7:
If we divide 750 by 77, we get 9 and a remainder of 57.
Record the quotient 9 as the next digit in the result. 
Result so far: 1681.9
The remainder is 57 after subtracting 693 from 750.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

Going ahead to step 8:
77 can be fit into 570 7 times, resulting in a remainder of 31.
Write down 7 as next digit of the result. 
Result so far: 1681.97
If we take 539 away from 570, we end up with 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Step 9:
When dividing 310 by 77, we get 4 with a remainder of 2.
The number 4 becomes the next digit in our result. 
Result so far: 1681.974
The remainder is 2 after subtracting 308 from 310.
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 10:
77 goes into 20 0 times with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 1681.974
If we subtract 0 from 20, we get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 11:
The number 77 fits into 200 2 times, leaving a remainder of 46.
The number 2 becomes the next digit in our result. 
Result so far: 1681.97402
If we subtract 154 from 200, we 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.

Going ahead to step 12:
The number 77 fits into 460 5 times, leaving a remainder of 75.
Put 5 as the next digit of the answer. 
Result so far: 1681.974025
Subtracting 385 from 460 leaves us with 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

On to step 13:
When dividing 750 by 77, we get 9 with a remainder of 57.
Use 9 as the next digit of our solution. 
Result so far: 1681.9740259
Deduct 693 from 750 and we're left with 57.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

Advancing to step 14:
77 can be fit into 570 7 times, resulting in a remainder of 31.
The next digit of our result is 7. 
Result so far: 1681.97402597
If we subtract 539 from 570, we get 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Our division results in 1681.97402597 with a remaining 3.1e-08.