We look at the division of 9381 by 81 
The aim is to understand the frequency of 81 in 9381.

Going ahead to step 1:
81 goes into 9 0 times with a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 9, we get 9.
Grab the next digit (3) from the dividend, add it to 9, then carry on: 93 / 81

On to step 2:
93 divided by 81 is 1 with a remainder of 12.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 81 away from 93, we end up with 12.
Grab the next digit (8) from the dividend, add it to 12, then carry on: 128 / 81

Let's proceed to step 3:
If we divide 128 by 81, we get 1 and a remainder of 47.
Put 1 as the next digit of the answer. 
Result so far: 11.0
Subtract 81 from 128 to get 47.
Append the next digit (1) from the dividend to 47 and continue with: 471 / 81

On to step 4:
471 divided by 81 is 5 with a remainder of 66.
Record the quotient 5 as the next digit in the result. 
Result so far: 115.0
If we subtract 405 from 471, we get 66.
Since there are no more digits in the dividend, we add a zero to the remainder making it 660, and continue the process.

Advancing to step 5:
81 can be fit into 660 8 times, resulting in a remainder of 12.
Record the quotient 8 as the next digit in the result. 
Result so far: 115.8
Subtracting 648 from 660 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.

Moving on to step 6:
81 can be fit into 120 1 times, resulting in a remainder of 39.
Put 1 as the next digit of the answer. 
Result so far: 115.81
Subtracting 81 from 120 leaves us with 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Let's proceed to step 7:
390 divided by 81 is 4 with a remainder of 66.
Record the quotient 4 as the next digit in the result. 
Result so far: 115.814
If we take 324 away from 390, we end up with 66.
Since there are no more digits in the dividend, we add a zero to the remainder making it 660, and continue the process.

Advancing to step 8:
81 can be fit into 660 8 times, resulting in a remainder of 12.
The number 8 becomes the next digit in our result. 
Result so far: 115.8148
If we take 648 away from 660, we end up 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:
When dividing 120 by 81, we get 1 with a remainder of 39.
Put 1 as the next digit of the answer. 
Result so far: 115.81481
If we subtract 81 from 120, we get 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Moving on to step 10:
When dividing 390 by 81, we get 4 with a remainder of 66.
The number 4 becomes the next digit in our result. 
Result so far: 115.814814
Subtracting 324 from 390 leaves us with 66.
Since there are no more digits in the dividend, we add a zero to the remainder making it 660, and continue the process.

Moving on to step 11:
The number 81 fits into 660 8 times, leaving a remainder of 12.
The number 8 becomes the next digit in our result. 
Result so far: 115.8148148
If we subtract 648 from 660, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 12:
120 divided by 81 is 1 with a remainder of 39.
The number 1 becomes the next digit in our result. 
Result so far: 115.81481481
Deduct 81 from 120 and we're left with 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Our division results in 115.81481481 with a remaining 3.9e-08.