We look at the division of 345520 by 86 
The aim is to understand the frequency of 86 in 345520.

On to step 1:
If we divide 3 by 86, we get 0 and a remainder of 3.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Append the next digit (4) from the dividend to 3 and continue with: 34 / 86

Moving on to step 2:
86 can be fit into 34 0 times, resulting in a remainder of 34.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 34 and we're left with 34.
Grab the next digit (5) from the dividend, add it to 34, then carry on: 345 / 86

Going ahead to step 3:
The number 86 fits into 345 4 times, leaving a remainder of 1.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
Deduct 344 from 345 and we're left with 1.
Grab the next digit (5) from the dividend, add it to 1, then carry on: 15 / 86

Step 4:
86 can be fit into 15 0 times, resulting in a remainder of 15.
Record the quotient 0 as the next digit in the result. 
Result so far: 40.0
Subtract 0 from 15 to get 15.
Append the next digit (2) from the dividend to 15 and continue with: 152 / 86

Step 5:
86 goes into 152 1 times with a remainder of 66.
The next digit of our result is 1. 
Result so far: 401.0
Subtracting 86 from 152 leaves us with 66.
Include the next digit (0) from the dividend after 66, then repeat: 660 / 86

On to step 6:
If we divide 660 by 86, we get 7 and a remainder of 58.
The number 7 becomes the next digit in our result. 
Result so far: 4017.0
Deduct 602 from 660 and we're left with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Advancing to step 7:
The number 86 fits into 580 6 times, leaving a remainder of 64.
Use 6 as the next digit of our solution. 
Result so far: 4017.6
Subtracting 516 from 580 leaves us with 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Going ahead to step 8:
86 can be fit into 640 7 times, resulting in a remainder of 38.
The next digit of our result is 7. 
Result so far: 4017.67
If we subtract 602 from 640, we get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Advancing to step 9:
The number 86 fits into 380 4 times, leaving a remainder of 36.
The next digit of our result is 4. 
Result so far: 4017.674
If we take 344 away from 380, we end up with 36.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Advancing to step 10:
360 divided by 86 is 4 with a remainder of 16.
Record the quotient 4 as the next digit in the result. 
Result so far: 4017.6744
If we take 344 away from 360, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Our division results in 4017.6744 with a remaining 0.00016.