We look at the division of 307812 by 86 
The aim is to understand the frequency of 86 in 307812.

On to step 1:
3 divided by 86 is 0 with a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Fetch the next digit (0) from the dividend, attach it to 3 and continue: 30 / 86

On to step 2:
When dividing 30 by 86, we get 0 with a remainder of 30.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 30, we get 30.
Take the next digit (7) from the dividend and append it to 30, then repeat: 307 / 86

On to step 3:
If we divide 307 by 86, we get 3 and a remainder of 49.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
Subtract 258 from 307 to get 49.
Include the next digit (8) from the dividend after 49, then repeat: 498 / 86

On to step 4:
When dividing 498 by 86, we get 5 with a remainder of 68.
Record the quotient 5 as the next digit in the result. 
Result so far: 35.0
Deduct 430 from 498 and we're left with 68.
Take the next digit (1) from the dividend and append it to 68, then repeat: 681 / 86

Advancing to step 5:
86 goes into 681 7 times with a remainder of 79.
The number 7 becomes the next digit in our result. 
Result so far: 357.0
If we subtract 602 from 681, we get 79.
Append the next digit (2) from the dividend to 79 and continue with: 792 / 86

Moving on to step 6:
86 goes into 792 9 times with a remainder of 18.
Use 9 as the next digit of our solution. 
Result so far: 3579.0
If we take 774 away from 792, we end up with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 7:
180 divided by 86 is 2 with a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 3579.2
Subtract 172 from 180 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 8:
The number 86 fits into 80 0 times, leaving a remainder of 80.
The number 0 becomes the next digit in our result. 
Result so far: 3579.2
If we take 0 away from 80, we end up with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Step 9:
86 can be fit into 800 9 times, resulting in a remainder of 26.
The number 9 becomes the next digit in our result. 
Result so far: 3579.209
If we subtract 774 from 800, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Let's proceed to step 10:
86 can be fit into 260 3 times, resulting in a remainder of 2.
The number 3 becomes the next digit in our result. 
Result so far: 3579.2093
Deduct 258 from 260 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 11:
86 goes into 20 0 times with a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 3579.2093
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 12:
200 divided by 86 is 2 with a remainder of 28.
Put 2 as the next digit of the answer. 
Result so far: 3579.209302
The remainder is 28 after subtracting 172 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

Moving on to step 13:
280 divided by 86 is 3 with a remainder of 22.
The number 3 becomes the next digit in our result. 
Result so far: 3579.2093023
The remainder is 22 after subtracting 258 from 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

On to step 14:
86 can be fit into 220 2 times, resulting in a remainder of 48.
Record the quotient 2 as the next digit in the result. 
Result so far: 3579.20930232
Deduct 172 from 220 and we're left with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

In conclusion, the division gives 3579.20930232 with a balance of 4.8e-08.