We look at the division of 878088 by 25 
The aim is to understand the frequency of 25 in 878088.

Moving on to step 1:
When dividing 8 by 25, we get 0 with a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Take the next digit (7) from the dividend and append it to 8, then repeat: 87 / 25

On to step 2:
If we divide 87 by 25, we get 3 and a remainder of 12.
The next digit of our result is 3. 
Result so far: 3.0
The remainder is 12 after subtracting 75 from 87.
Include the next digit (8) from the dividend after 12, then repeat: 128 / 25

Advancing to step 3:
If we divide 128 by 25, we get 5 and a remainder of 3.
Record the quotient 5 as the next digit in the result. 
Result so far: 35.0
If we subtract 125 from 128, we get 3.
Take the next digit (0) from the dividend and append it to 3, then repeat: 30 / 25

Step 4:
The number 25 fits into 30 1 times, leaving a remainder of 5.
The number 1 becomes the next digit in our result. 
Result so far: 351.0
If we take 25 away from 30, we end up with 5.
Bring next digit (8) of the dividend behind the 5 and repeat the process: 58 / 25

Moving on to step 5:
If we divide 58 by 25, we get 2 and a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 3512.0
The remainder is 8 after subtracting 50 from 58.
Fetch the next digit (8) from the dividend, attach it to 8 and continue: 88 / 25

On to step 6:
88 divided by 25 is 3 with a remainder of 13.
The next digit of our result is 3. 
Result so far: 35123.0
If we subtract 75 from 88, we get 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Going ahead to step 7:
The number 25 fits into 130 5 times, leaving a remainder of 5.
The next digit of our result is 5. 
Result so far: 35123.5
Deduct 125 from 130 and we're left with 5.
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 8:
25 can be fit into 50 2 times, resulting in a remainder of 0.
Use 2 as the next digit of our solution. 
Result so far: 35123.52
Subtracting 50 from 50 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 9:
0 divided by 25 is 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 35123.52
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 10:
If we divide 0 by 25, we get 0 and a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 35123.52
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The quotient of the division is 35123.52, and the remainder is 0.0.