We're dividing 742836 by 81 
The aim is to understand the frequency of 81 in 742836.

On to step 1:
When dividing 7 by 81, we get 0 with a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 7, we end up with 7.
Fetch the next digit (4) from the dividend, attach it to 7 and continue: 74 / 81

On to step 2:
If we divide 74 by 81, we get 0 and a remainder of 74.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 74 leaves us with 74.
Fetch the next digit (2) from the dividend, attach it to 74 and continue: 742 / 81

Let's proceed to step 3:
If we divide 742 by 81, we get 9 and a remainder of 13.
Write down 9 as next digit of the result. 
Result so far: 9.0
If we take 729 away from 742, we end up with 13.
Include the next digit (8) from the dividend after 13, then repeat: 138 / 81

Advancing to step 4:
When dividing 138 by 81, we get 1 with a remainder of 57.
The number 1 becomes the next digit in our result. 
Result so far: 91.0
Subtract 81 from 138 to get 57.
Bring next digit (3) of the dividend behind the 57 and repeat the process: 573 / 81

Moving on to step 5:
If we divide 573 by 81, we get 7 and a remainder of 6.
The next digit of our result is 7. 
Result so far: 917.0
If we take 567 away from 573, we end up with 6.
Take the next digit (6) from the dividend and append it to 6, then repeat: 66 / 81

Moving on to step 6:
81 goes into 66 0 times with a remainder of 66.
Write down 0 as next digit of the result. 
Result so far: 9170.0
Subtracting 0 from 66 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.

Let's proceed to step 7:
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: 9170.8
The remainder is 12 after subtracting 648 from 660.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 8:
If we divide 120 by 81, we get 1 and a remainder of 39.
The number 1 becomes the next digit in our result. 
Result so far: 9170.81
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.

Moving on to step 9:
390 divided by 81 is 4 with a remainder of 66.
Put 4 as the next digit of the answer. 
Result so far: 9170.814
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.

Step 10:
The number 81 fits into 660 8 times, leaving a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 9170.8148
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.

Advancing to step 11:
81 goes into 120 1 times with a remainder of 39.
Use 1 as the next digit of our solution. 
Result so far: 9170.81481
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.

Going ahead to step 12:
The number 81 fits into 390 4 times, leaving a remainder of 66.
Use 4 as the next digit of our solution. 
Result so far: 9170.814814
Deduct 324 from 390 and we're left 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.

Going ahead to step 13:
If we divide 660 by 81, we get 8 and a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 9170.8148148
Subtract 648 from 660 to 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 14:
If we divide 120 by 81, we get 1 and a remainder of 39.
Record the quotient 1 as the next digit in the result. 
Result so far: 9170.81481481
Subtract 81 from 120 to 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.

Our division results in 9170.81481481 with a remaining 3.9e-08.