We're dividing 180731 by 81 
The aim is to understand the frequency of 81 in 180731.

Step 1:
If we divide 1 by 81, we get 0 and a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Grab the next digit (8) from the dividend, add it to 1, then carry on: 18 / 81

Going ahead to step 2:
If we divide 18 by 81, we get 0 and a remainder of 18.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 18 and we're left with 18.
Bring next digit (0) of the dividend behind the 18 and repeat the process: 180 / 81

On to step 3:
81 can be fit into 180 2 times, resulting in a remainder of 18.
Use 2 as the next digit of our solution. 
Result so far: 2.0
Deduct 162 from 180 and we're left with 18.
Take the next digit (7) from the dividend and append it to 18, then repeat: 187 / 81

Advancing to step 4:
If we divide 187 by 81, we get 2 and a remainder of 25.
Use 2 as the next digit of our solution. 
Result so far: 22.0
Subtracting 162 from 187 leaves us with 25.
Bring next digit (3) of the dividend behind the 25 and repeat the process: 253 / 81

Let's proceed to step 5:
81 can be fit into 253 3 times, resulting in a remainder of 10.
Write down 3 as next digit of the result. 
Result so far: 223.0
Subtract 243 from 253 to get 10.
Fetch the next digit (1) from the dividend, attach it to 10 and continue: 101 / 81

Going ahead to step 6:
101 divided by 81 is 1 with a remainder of 20.
Put 1 as the next digit of the answer. 
Result so far: 2231.0
Subtract 81 from 101 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Let's proceed to step 7:
81 can be fit into 200 2 times, resulting in a remainder of 38.
The number 2 becomes the next digit in our result. 
Result so far: 2231.2
If we take 162 away from 200, we end up with 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

On to step 8:
When dividing 380 by 81, we get 4 with a remainder of 56.
Use 4 as the next digit of our solution. 
Result so far: 2231.24
Subtract 324 from 380 to get 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Going ahead to step 9:
If we divide 560 by 81, we get 6 and a remainder of 74.
Record the quotient 6 as the next digit in the result. 
Result so far: 2231.246
If we take 486 away from 560, we end up with 74.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Moving on to step 10:
When dividing 740 by 81, we get 9 with a remainder of 11.
The next digit of our result is 9. 
Result so far: 2231.2469
Deduct 729 from 740 and we're left with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Advancing to step 11:
If we divide 110 by 81, we get 1 and a remainder of 29.
Record the quotient 1 as the next digit in the result. 
Result so far: 2231.24691
Subtract 81 from 110 to get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Step 12:
If we divide 290 by 81, we get 3 and a remainder of 47.
The number 3 becomes the next digit in our result. 
Result so far: 2231.246913
If we subtract 243 from 290, we get 47.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

Advancing to step 13:
When dividing 470 by 81, we get 5 with a remainder of 65.
The number 5 becomes the next digit in our result. 
Result so far: 2231.2469135
Subtracting 405 from 470 leaves us with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Advancing to step 14:
81 goes into 650 8 times with a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 2231.24691358
If we take 648 away from 650, we end up with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

After the division, we end up with 2231.24691358 and a remainder of 2e-09.