423961 ÷ 75 
The aim is to understand the frequency of 75 in 423961.

Moving on to step 1:
If we divide 4 by 75, we get 0 and a remainder of 4.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 4, we get 4.
Fetch the next digit (2) from the dividend, attach it to 4 and continue: 42 / 75

Step 2:
42 divided by 75 is 0 with a remainder of 42.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 42, we end up with 42.
Append the next digit (3) from the dividend to 42 and continue with: 423 / 75

On to step 3:
When dividing 423 by 75, we get 5 with a remainder of 48.
Write down 5 as next digit of the result. 
Result so far: 5.0
Subtract 375 from 423 to get 48.
Append the next digit (9) from the dividend to 48 and continue with: 489 / 75

Moving on to step 4:
489 divided by 75 is 6 with a remainder of 39.
Put 6 as the next digit of the answer. 
Result so far: 56.0
Subtracting 450 from 489 leaves us with 39.
Include the next digit (6) from the dividend after 39, then repeat: 396 / 75

On to step 5:
When dividing 396 by 75, we get 5 with a remainder of 21.
Put 5 as the next digit of the answer. 
Result so far: 565.0
Deduct 375 from 396 and we're left with 21.
Append the next digit (1) from the dividend to 21 and continue with: 211 / 75

Going ahead to step 6:
211 divided by 75 is 2 with a remainder of 61.
Put 2 as the next digit of the answer. 
Result so far: 5652.0
If we subtract 150 from 211, we get 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Going ahead to step 7:
The number 75 fits into 610 8 times, leaving a remainder of 10.
Put 8 as the next digit of the answer. 
Result so far: 5652.8
Subtract 600 from 610 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 8:
If we divide 100 by 75, we get 1 and a remainder of 25.
Write down 1 as next digit of the result. 
Result so far: 5652.81
Subtracting 75 from 100 leaves us 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.

Advancing to step 9:
75 can be fit into 250 3 times, resulting in a remainder of 25.
Record the quotient 3 as the next digit in the result. 
Result so far: 5652.813
Subtracting 225 from 250 leaves us 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.

Let's proceed to step 10:
75 can be fit into 250 3 times, resulting in a remainder of 25.
The next digit of our result is 3. 
Result so far: 5652.8133
Deduct 225 from 250 and we're left 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.

The final result is 5652.8133 with a remainder of 0.00025.