We're dividing 28709086 by 525 
The aim is to understand the frequency of 525 in 28709086.

Advancing to step 1:
525 goes into 2 0 times with a remainder of 2.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Grab the next digit (8) from the dividend, add it to 2, then carry on: 28 / 525

Going ahead to step 2:
The number 525 fits into 28 0 times, leaving a remainder of 28.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 28 and we're left with 28.
Append the next digit (7) from the dividend to 28 and continue with: 287 / 525

Going ahead to step 3:
525 can be fit into 287 0 times, resulting in a remainder of 287.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 287 to get 287.
Include the next digit (0) from the dividend after 287, then repeat: 2870 / 525

Step 4:
The number 525 fits into 2870 5 times, leaving a remainder of 245.
Write down 5 as next digit of the result. 
Result so far: 5.0
Subtract 2625 from 2870 to get 245.
Fetch the next digit (9) from the dividend, attach it to 245 and continue: 2459 / 525

Going ahead to step 5:
525 can be fit into 2459 4 times, resulting in a remainder of 359.
The next digit of our result is 4. 
Result so far: 54.0
The remainder is 359 after subtracting 2100 from 2459.
Grab the next digit (0) from the dividend, add it to 359, then carry on: 3590 / 525

Going ahead to step 6:
When dividing 3590 by 525, we get 6 with a remainder of 440.
The next digit of our result is 6. 
Result so far: 546.0
If we subtract 3150 from 3590, we get 440.
Take the next digit (8) from the dividend and append it to 440, then repeat: 4408 / 525

On to step 7:
525 can be fit into 4408 8 times, resulting in a remainder of 208.
The number 8 becomes the next digit in our result. 
Result so far: 5468.0
The remainder is 208 after subtracting 4200 from 4408.
Append the next digit (6) from the dividend to 208 and continue with: 2086 / 525

Let's proceed to step 8:
The number 525 fits into 2086 3 times, leaving a remainder of 511.
Use 3 as the next digit of our solution. 
Result so far: 54683.0
Subtracting 1575 from 2086 leaves us with 511.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5110, and continue the process.

On to step 9:
525 goes into 5110 9 times with a remainder of 385.
Use 9 as the next digit of our solution. 
Result so far: 54683.9
Subtracting 4725 from 5110 leaves us with 385.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3850, and continue the process.

Going ahead to step 10:
The number 525 fits into 3850 7 times, leaving a remainder of 175.
Put 7 as the next digit of the answer. 
Result so far: 54683.97
The remainder is 175 after subtracting 3675 from 3850.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1750, and continue the process.

Let's proceed to step 11:
When dividing 1750 by 525, we get 3 with a remainder of 175.
Put 3 as the next digit of the answer. 
Result so far: 54683.973
Subtract 1575 from 1750 to get 175.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1750, and continue the process.

Advancing to step 12:
When dividing 1750 by 525, we get 3 with a remainder of 175.
The number 3 becomes the next digit in our result. 
Result so far: 54683.9733
Deduct 1575 from 1750 and we're left with 175.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1750, and continue the process.

After the division, we end up with 54683.9733 and a remainder of 0.00175.