731608 divided by 81 
The aim is to understand the frequency of 81 in 731608.

Moving on to step 1:
When dividing 7 by 81, we get 0 with a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Bring next digit (3) of the dividend behind the 7 and repeat the process: 73 / 81

Going ahead to step 2:
If we divide 73 by 81, we get 0 and a remainder of 73.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 73, we get 73.
Take the next digit (1) from the dividend and append it to 73, then repeat: 731 / 81

On to step 3:
The number 81 fits into 731 9 times, leaving a remainder of 2.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
If we take 729 away from 731, we end up with 2.
Fetch the next digit (6) from the dividend, attach it to 2 and continue: 26 / 81

On to step 4:
26 divided by 81 is 0 with a remainder of 26.
Put 0 as the next digit of the answer. 
Result so far: 90.0
If we subtract 0 from 26, we get 26.
Include the next digit (0) from the dividend after 26, then repeat: 260 / 81

Advancing to step 5:
260 divided by 81 is 3 with a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 903.0
If we take 243 away from 260, we end up with 17.
Append the next digit (8) from the dividend to 17 and continue with: 178 / 81

Moving on to step 6:
81 goes into 178 2 times with a remainder of 16.
Record the quotient 2 as the next digit in the result. 
Result so far: 9032.0
The remainder is 16 after subtracting 162 from 178.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 7:
The number 81 fits into 160 1 times, leaving a remainder of 79.
The next digit of our result is 1. 
Result so far: 9032.1
Deduct 81 from 160 and we're left with 79.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

Step 8:
790 divided by 81 is 9 with a remainder of 61.
The number 9 becomes the next digit in our result. 
Result so far: 9032.19
If we take 729 away from 790, we end up with 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Step 9:
When dividing 610 by 81, we get 7 with a remainder of 43.
Record the quotient 7 as the next digit in the result. 
Result so far: 9032.197
If we take 567 away from 610, we end up with 43.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

On to step 10:
If we divide 430 by 81, we get 5 and a remainder of 25.
The next digit of our result is 5. 
Result so far: 9032.1975
If we take 405 away from 430, we end up with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Let's proceed to step 11:
The number 81 fits into 250 3 times, leaving a remainder of 7.
Record the quotient 3 as the next digit in the result. 
Result so far: 9032.19753
Subtracting 243 from 250 leaves us with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Moving on to step 12:
If we divide 70 by 81, we get 0 and a remainder of 70.
The next digit of our result is 0. 
Result so far: 9032.19753
Subtract 0 from 70 to get 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Going ahead to step 13:
81 goes into 700 8 times with a remainder of 52.
Record the quotient 8 as the next digit in the result. 
Result so far: 9032.1975308
If we subtract 648 from 700, we get 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Going ahead to step 14:
81 can be fit into 520 6 times, resulting in a remainder of 34.
The next digit of our result is 6. 
Result so far: 9032.19753086
If we subtract 486 from 520, we get 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

The final outcome is 9032.19753086, with a leftover of 3.4e-08.