We're dividing 167991 by 20 
We want to divide 167991 by 20.

Going ahead to step 1:
20 can be fit into 1 0 times, resulting in a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Fetch the next digit (6) from the dividend, attach it to 1 and continue: 16 / 20

On to step 2:
If we divide 16 by 20, we get 0 and a remainder of 16.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 16 leaves us with 16.
Bring next digit (7) of the dividend behind the 16 and repeat the process: 167 / 20

Let's proceed to step 3:
If we divide 167 by 20, we get 8 and a remainder of 7.
The number 8 becomes the next digit in our result. 
Result so far: 8.0
The remainder is 7 after subtracting 160 from 167.
Include the next digit (9) from the dividend after 7, then repeat: 79 / 20

On to step 4:
If we divide 79 by 20, we get 3 and a remainder of 19.
The number 3 becomes the next digit in our result. 
Result so far: 83.0
If we take 60 away from 79, we end up with 19.
Take the next digit (9) from the dividend and append it to 19, then repeat: 199 / 20

Advancing to step 5:
20 can be fit into 199 9 times, resulting in a remainder of 19.
The number 9 becomes the next digit in our result. 
Result so far: 839.0
If we take 180 away from 199, we end up with 19.
Bring next digit (1) of the dividend behind the 19 and repeat the process: 191 / 20

Step 6:
The number 20 fits into 191 9 times, leaving a remainder of 11.
Put 9 as the next digit of the answer. 
Result so far: 8399.0
Deduct 180 from 191 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.

Let's proceed to step 7:
The number 20 fits into 110 5 times, leaving a remainder of 10.
Use 5 as the next digit of our solution. 
Result so far: 8399.5
Subtracting 100 from 110 leaves us 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.

On to step 8:
If we divide 100 by 20, we get 5 and a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 8399.55
The remainder is 0 after subtracting 100 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 8399.55, with a leftover of 0.0.