Let's divide 873799 by 18
The aim is to understand the frequency of 18 in 873799.

Step 1:
18 goes into 8 0 times with a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Append the next digit (7) from the dividend to 8 and continue with: 87 / 18

Moving on to step 2:
18 goes into 87 4 times with a remainder of 15.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
If we take 72 away from 87, we end up with 15.
Fetch the next digit (3) from the dividend, attach it to 15 and continue: 153 / 18

Going ahead to step 3:
153 divided by 18 is 8 with a remainder of 9.
Use 8 as the next digit of our solution. 
Result so far: 48.0
Deduct 144 from 153 and we're left with 9.
Take the next digit (7) from the dividend and append it to 9, then repeat: 97 / 18

Going ahead to step 4:
When dividing 97 by 18, we get 5 with a remainder of 7.
The next digit of our result is 5. 
Result so far: 485.0
Subtracting 90 from 97 leaves us with 7.
Grab the next digit (9) from the dividend, add it to 7, then carry on: 79 / 18

On to step 5:
18 can be fit into 79 4 times, resulting in a remainder of 7.
The number 4 becomes the next digit in our result. 
Result so far: 4854.0
Subtract 72 from 79 to get 7.
Fetch the next digit (9) from the dividend, attach it to 7 and continue: 79 / 18

On to step 6:
18 goes into 79 4 times with a remainder of 7.
Write down 4 as next digit of the result. 
Result so far: 48544.0
Subtract 72 from 79 to get 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 7:
18 goes into 70 3 times with a remainder of 16.
Use 3 as the next digit of our solution. 
Result so far: 48544.3
If we take 54 away from 70, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Step 8:
18 can be fit into 160 8 times, resulting in a remainder of 16.
The number 8 becomes the next digit in our result. 
Result so far: 48544.38
Subtracting 144 from 160 leaves us with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 9:
18 goes into 160 8 times with a remainder of 16.
The next digit of our result is 8. 
Result so far: 48544.388
Subtract 144 from 160 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

The quotient of the division is 48544.388, and the remainder is 0.0016.