72181052 ÷ 18 
The aim is to understand the frequency of 18 in 72181052.

Going ahead to step 1:
18 goes into 7 0 times with a remainder of 7.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Include the next digit (2) from the dividend after 7, then repeat: 72 / 18

Going ahead to step 2:
72 divided by 18 is 4 with a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
The remainder is 0 after subtracting 72 from 72.
Include the next digit (1) from the dividend after 0, then repeat: 1 / 18

Moving on to step 3:
The number 18 fits into 1 0 times, leaving a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 40.0
Subtracting 0 from 1 leaves us with 1.
Append the next digit (8) from the dividend to 1 and continue with: 18 / 18

Moving on to step 4:
18 goes into 18 1 times with a remainder of 0.
Use 1 as the next digit of our solution. 
Result so far: 401.0
If we take 18 away from 18, we end up with 0.
Grab the next digit (1) from the dividend, add it to 0, then carry on: 1 / 18

Going ahead to step 5:
1 divided by 18 is 0 with a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 4010.0
If we subtract 0 from 1, we get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 18

Advancing to step 6:
18 can be fit into 10 0 times, resulting in a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 40100.0
The remainder is 10 after subtracting 0 from 10.
Grab the next digit (5) from the dividend, add it to 10, then carry on: 105 / 18

Moving on to step 7:
18 can be fit into 105 5 times, resulting in a remainder of 15.
Put 5 as the next digit of the answer. 
Result so far: 401005.0
Deduct 90 from 105 and we're left with 15.
Bring next digit (2) of the dividend behind the 15 and repeat the process: 152 / 18

On to step 8:
If we divide 152 by 18, we get 8 and a remainder of 8.
Use 8 as the next digit of our solution. 
Result so far: 4010058.0
Subtracting 144 from 152 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

On to step 9:
If we divide 80 by 18, we get 4 and a remainder of 8.
Use 4 as the next digit of our solution. 
Result so far: 4010058.4
Subtracting 72 from 80 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 10:
18 goes into 80 4 times with a remainder of 8.
Record the quotient 4 as the next digit in the result. 
Result so far: 4010058.44
Subtracting 72 from 80 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

The final result is 4010058.44 with a remainder of 0.008.