We're dividing 640750 by 86 
The aim is to understand the frequency of 86 in 640750.

On to step 1:
86 goes into 6 0 times with a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Take the next digit (4) from the dividend and append it to 6, then repeat: 64 / 86

Moving on to step 2:
64 divided by 86 is 0 with a remainder of 64.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 64 and we're left with 64.
Fetch the next digit (0) from the dividend, attach it to 64 and continue: 640 / 86

On to step 3:
86 goes into 640 7 times with a remainder of 38.
The number 7 becomes the next digit in our result. 
Result so far: 7.0
Subtracting 602 from 640 leaves us with 38.
Grab the next digit (7) from the dividend, add it to 38, then carry on: 387 / 86

Advancing to step 4:
86 goes into 387 4 times with a remainder of 43.
Write down 4 as next digit of the result. 
Result so far: 74.0
If we subtract 344 from 387, we get 43.
Fetch the next digit (5) from the dividend, attach it to 43 and continue: 435 / 86

On to step 5:
When dividing 435 by 86, we get 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 745.0
The remainder is 5 after subtracting 430 from 435.
Append the next digit (0) from the dividend to 5 and continue with: 50 / 86

Moving on to step 6:
The number 86 fits into 50 0 times, leaving a remainder of 50.
Put 0 as the next digit of the answer. 
Result so far: 7450.0
Subtract 0 from 50 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Advancing to step 7:
The number 86 fits into 500 5 times, leaving a remainder of 70.
The number 5 becomes the next digit in our result. 
Result so far: 7450.5
Deduct 430 from 500 and we're left 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.

Let's proceed to step 8:
If we divide 700 by 86, we get 8 and a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 7450.58
Subtracting 688 from 700 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Let's proceed to step 9:
120 divided by 86 is 1 with a remainder of 34.
The next digit of our result is 1. 
Result so far: 7450.581
Subtracting 86 from 120 leaves us with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

On to step 10:
340 divided by 86 is 3 with a remainder of 82.
The number 3 becomes the next digit in our result. 
Result so far: 7450.5813
If we subtract 258 from 340, we get 82.
Since there are no more digits in the dividend, we add a zero to the remainder making it 820, and continue the process.

Step 11:
820 divided by 86 is 9 with a remainder of 46.
The next digit of our result is 9. 
Result so far: 7450.58139
Deduct 774 from 820 and we're left with 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 460, and continue the process.

Step 12:
460 divided by 86 is 5 with a remainder of 30.
Use 5 as the next digit of our solution. 
Result so far: 7450.581395
Deduct 430 from 460 and we're left with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

On to step 13:
300 divided by 86 is 3 with a remainder of 42.
The number 3 becomes the next digit in our result. 
Result so far: 7450.5813953
The remainder is 42 after subtracting 258 from 300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Moving on to step 14:
If we divide 420 by 86, we get 4 and a remainder of 76.
Put 4 as the next digit of the answer. 
Result so far: 7450.58139534
Deduct 344 from 420 and we're left with 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

The final result is 7450.58139534 with a remainder of 7.6e-08.