We look at the division of 142885 by 18 
The aim is to understand the frequency of 18 in 142885.

On to step 1:
When dividing 1 by 18, we get 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Append the next digit (4) from the dividend to 1 and continue with: 14 / 18

Let's proceed to step 2:
14 divided by 18 is 0 with a remainder of 14.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 14, we get 14.
Append the next digit (2) from the dividend to 14 and continue with: 142 / 18

Moving on to step 3:
If we divide 142 by 18, we get 7 and a remainder of 16.
Use 7 as the next digit of our solution. 
Result so far: 7.0
Subtract 126 from 142 to get 16.
Fetch the next digit (8) from the dividend, attach it to 16 and continue: 168 / 18

Going ahead to step 4:
168 divided by 18 is 9 with a remainder of 6.
Write down 9 as next digit of the result. 
Result so far: 79.0
Deduct 162 from 168 and we're left with 6.
Fetch the next digit (8) from the dividend, attach it to 6 and continue: 68 / 18

Let's proceed to step 5:
The number 18 fits into 68 3 times, leaving a remainder of 14.
Use 3 as the next digit of our solution. 
Result so far: 793.0
Deduct 54 from 68 and we're left with 14.
Bring next digit (5) of the dividend behind the 14 and repeat the process: 145 / 18

Moving on to step 6:
18 goes into 145 8 times with a remainder of 1.
Write down 8 as next digit of the result. 
Result so far: 7938.0
Subtract 144 from 145 to get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 7:
If we divide 10 by 18, we get 0 and a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 7938.0
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 8:
18 can be fit into 100 5 times, resulting in a remainder of 10.
Use 5 as the next digit of our solution. 
Result so far: 7938.05
Deduct 90 from 100 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 9:
100 divided by 18 is 5 with a remainder of 10.
Record the quotient 5 as the next digit in the result. 
Result so far: 7938.055
If we take 90 away from 100, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final outcome is 7938.055, with a leftover of 0.001.