391567 ÷ 75 
The aim is to understand the frequency of 75 in 391567.

Going ahead to step 1:
75 goes into 3 0 times with a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Include the next digit (9) from the dividend after 3, then repeat: 39 / 75

Advancing to step 2:
The number 75 fits into 39 0 times, leaving a remainder of 39.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 39 to get 39.
Fetch the next digit (1) from the dividend, attach it to 39 and continue: 391 / 75

Step 3:
75 can be fit into 391 5 times, resulting in a remainder of 16.
The next digit of our result is 5. 
Result so far: 5.0
Deduct 375 from 391 and we're left with 16.
Take the next digit (5) from the dividend and append it to 16, then repeat: 165 / 75

Step 4:
75 can be fit into 165 2 times, resulting in a remainder of 15.
Record the quotient 2 as the next digit in the result. 
Result so far: 52.0
Subtract 150 from 165 to get 15.
Include the next digit (6) from the dividend after 15, then repeat: 156 / 75

Step 5:
75 can be fit into 156 2 times, resulting in a remainder of 6.
The number 2 becomes the next digit in our result. 
Result so far: 522.0
Subtracting 150 from 156 leaves us with 6.
Append the next digit (7) from the dividend to 6 and continue with: 67 / 75

Moving on to step 6:
75 goes into 67 0 times with a remainder of 67.
The number 0 becomes the next digit in our result. 
Result so far: 5220.0
Subtracting 0 from 67 leaves us with 67.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

Going ahead to step 7:
75 can be fit into 670 8 times, resulting in a remainder of 70.
Put 8 as the next digit of the answer. 
Result so far: 5220.8
Subtracting 600 from 670 leaves us with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Step 8:
If we divide 700 by 75, we get 9 and a remainder of 25.
Write down 9 as next digit of the result. 
Result so far: 5220.89
The remainder is 25 after subtracting 675 from 700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Step 9:
When dividing 250 by 75, we get 3 with a remainder of 25.
The number 3 becomes the next digit in our result. 
Result so far: 5220.893
If we subtract 225 from 250, 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.

Step 10:
250 divided by 75 is 3 with a remainder of 25.
Use 3 as the next digit of our solution. 
Result so far: 5220.8933
If we take 225 away from 250, we end up with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

After the division, we end up with 5220.8933 and a remainder of 0.00025.