86836 ÷ 81 
The aim is to understand the frequency of 81 in 86836.

Moving on to step 1:
81 goes into 8 0 times with a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Grab the next digit (6) from the dividend, add it to 8, then carry on: 86 / 81

Going ahead to step 2:
81 goes into 86 1 times with a remainder of 5.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 81 from 86 to get 5.
Include the next digit (8) from the dividend after 5, then repeat: 58 / 81

Advancing to step 3:
58 divided by 81 is 0 with a remainder of 58.
The next digit of our result is 0. 
Result so far: 10.0
The remainder is 58 after subtracting 0 from 58.
Take the next digit (3) from the dividend and append it to 58, then repeat: 583 / 81

On to step 4:
81 goes into 583 7 times with a remainder of 16.
Write down 7 as next digit of the result. 
Result so far: 107.0
If we take 567 away from 583, we end up with 16.
Take the next digit (6) from the dividend and append it to 16, then repeat: 166 / 81

Step 5:
The number 81 fits into 166 2 times, leaving a remainder of 4.
Use 2 as the next digit of our solution. 
Result so far: 1072.0
Subtracting 162 from 166 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 6:
The number 81 fits into 40 0 times, leaving a remainder of 40.
Record the quotient 0 as the next digit in the result. 
Result so far: 1072.0
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Step 7:
81 can be fit into 400 4 times, resulting in a remainder of 76.
Write down 4 as next digit of the result. 
Result so far: 1072.04
Subtract 324 from 400 to get 76.
Since there are no more digits in the dividend, we add a zero to the remainder making it 760, and continue the process.

Let's proceed to step 8:
When dividing 760 by 81, we get 9 with a remainder of 31.
Put 9 as the next digit of the answer. 
Result so far: 1072.049
If we take 729 away from 760, we end up with 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Step 9:
If we divide 310 by 81, we get 3 and a remainder of 67.
The next digit of our result is 3. 
Result so far: 1072.0493
The remainder is 67 after subtracting 243 from 310.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

Let's proceed to step 10:
81 can be fit into 670 8 times, resulting in a remainder of 22.
Put 8 as the next digit of the answer. 
Result so far: 1072.04938
Subtract 648 from 670 to get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Moving on to step 11:
When dividing 220 by 81, we get 2 with a remainder of 58.
The number 2 becomes the next digit in our result. 
Result so far: 1072.049382
Deduct 162 from 220 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.

Let's proceed to step 12:
81 can be fit into 580 7 times, resulting in a remainder of 13.
The number 7 becomes the next digit in our result. 
Result so far: 1072.0493827
The remainder is 13 after subtracting 567 from 580.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Step 13:
The number 81 fits into 130 1 times, leaving a remainder of 49.
Put 1 as the next digit of the answer. 
Result so far: 1072.04938271
The remainder is 49 after subtracting 81 from 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

After the division, we end up with 1072.04938271 and a remainder of 4.9e-08.