We look at the division of 852453 by 81 
The aim is to understand the frequency of 81 in 852453.

Advancing to step 1:
81 can be fit into 8 0 times, resulting in a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Take the next digit (5) from the dividend and append it to 8, then repeat: 85 / 81

On to step 2:
If we divide 85 by 81, we get 1 and a remainder of 4.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtract 81 from 85 to get 4.
Take the next digit (2) from the dividend and append it to 4, then repeat: 42 / 81

On to step 3:
If we divide 42 by 81, we get 0 and a remainder of 42.
Use 0 as the next digit of our solution. 
Result so far: 10.0
Subtract 0 from 42 to get 42.
Include the next digit (4) from the dividend after 42, then repeat: 424 / 81

Moving on to step 4:
424 divided by 81 is 5 with a remainder of 19.
Write down 5 as next digit of the result. 
Result so far: 105.0
Deduct 405 from 424 and we're left with 19.
Bring next digit (5) of the dividend behind the 19 and repeat the process: 195 / 81

Advancing to step 5:
81 can be fit into 195 2 times, resulting in a remainder of 33.
Put 2 as the next digit of the answer. 
Result so far: 1052.0
The remainder is 33 after subtracting 162 from 195.
Append the next digit (3) from the dividend to 33 and continue with: 333 / 81

Moving on to step 6:
81 can be fit into 333 4 times, resulting in a remainder of 9.
The number 4 becomes the next digit in our result. 
Result so far: 10524.0
The remainder is 9 after subtracting 324 from 333.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 7:
90 divided by 81 is 1 with a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 10524.1
If we subtract 81 from 90, we get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

On to step 8:
When dividing 90 by 81, we get 1 with a remainder of 9.
The next digit of our result is 1. 
Result so far: 10524.11
Subtracting 81 from 90 leaves us with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

The quotient of the division is 10524.11, and the remainder is 0.009.