We look at the division of 77178825 by 515 
The aim is to understand the frequency of 515 in 77178825.

On to step 1:
When dividing 7 by 515, we get 0 with a remainder of 7.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 7 to get 7.
Take the next digit (7) from the dividend and append it to 7, then repeat: 77 / 515

Moving on to step 2:
515 can be fit into 77 0 times, resulting in a remainder of 77.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 77 to get 77.
Include the next digit (1) from the dividend after 77, then repeat: 771 / 515

Going ahead to step 3:
The number 515 fits into 771 1 times, leaving a remainder of 256.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 515 away from 771, we end up with 256.
Fetch the next digit (7) from the dividend, attach it to 256 and continue: 2567 / 515

Moving on to step 4:
When dividing 2567 by 515, we get 4 with a remainder of 507.
The number 4 becomes the next digit in our result. 
Result so far: 14.0
The remainder is 507 after subtracting 2060 from 2567.
Grab the next digit (8) from the dividend, add it to 507, then carry on: 5078 / 515

Let's proceed to step 5:
515 can be fit into 5078 9 times, resulting in a remainder of 443.
The next digit of our result is 9. 
Result so far: 149.0
If we take 4635 away from 5078, we end up with 443.
Include the next digit (8) from the dividend after 443, then repeat: 4438 / 515

Let's proceed to step 6:
515 can be fit into 4438 8 times, resulting in a remainder of 318.
Record the quotient 8 as the next digit in the result. 
Result so far: 1498.0
The remainder is 318 after subtracting 4120 from 4438.
Take the next digit (2) from the dividend and append it to 318, then repeat: 3182 / 515

Advancing to step 7:
515 goes into 3182 6 times with a remainder of 92.
The number 6 becomes the next digit in our result. 
Result so far: 14986.0
Subtract 3090 from 3182 to get 92.
Include the next digit (5) from the dividend after 92, then repeat: 925 / 515

Going ahead to step 8:
925 divided by 515 is 1 with a remainder of 410.
Write down 1 as next digit of the result. 
Result so far: 149861.0
Deduct 515 from 925 and we're left with 410.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4100, and continue the process.

Going ahead to step 9:
515 can be fit into 4100 7 times, resulting in a remainder of 495.
Use 7 as the next digit of our solution. 
Result so far: 149861.7
The remainder is 495 after subtracting 3605 from 4100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4950, and continue the process.

Step 10:
The number 515 fits into 4950 9 times, leaving a remainder of 315.
Record the quotient 9 as the next digit in the result. 
Result so far: 149861.79
If we take 4635 away from 4950, we end up with 315.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3150, and continue the process.

Going ahead to step 11:
3150 divided by 515 is 6 with a remainder of 60.
Write down 6 as next digit of the result. 
Result so far: 149861.796
The remainder is 60 after subtracting 3090 from 3150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Moving on to step 12:
When dividing 600 by 515, we get 1 with a remainder of 85.
Write down 1 as next digit of the result. 
Result so far: 149861.7961
Subtracting 515 from 600 leaves us with 85.
Since there are no more digits in the dividend, we add a zero to the remainder making it 850, and continue the process.

Advancing to step 13:
850 divided by 515 is 1 with a remainder of 335.
The number 1 becomes the next digit in our result. 
Result so far: 149861.79611
Subtracting 515 from 850 leaves us with 335.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3350, and continue the process.

Our division results in 149861.79611 with a remaining 0.000335.