We look at the division of 168503 by 21 
Let's see how many times 21 fits into 168503.

Moving on to step 1:
When dividing 1 by 21, we get 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Append the next digit (6) from the dividend to 1 and continue with: 16 / 21

On to step 2:
When dividing 16 by 21, we get 0 with a remainder of 16.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 16, we get 16.
Bring next digit (8) of the dividend behind the 16 and repeat the process: 168 / 21

Let's proceed to step 3:
If we divide 168 by 21, we get 8 and a remainder of 0.
Record the quotient 8 as the next digit in the result. 
Result so far: 8.0
Subtracting 168 from 168 leaves us with 0.
Include the next digit (5) from the dividend after 0, then repeat: 5 / 21

On to step 4:
The number 21 fits into 5 0 times, leaving a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 80.0
If we take 0 away from 5, we end up with 5.
Fetch the next digit (0) from the dividend, attach it to 5 and continue: 50 / 21

On to step 5:
50 divided by 21 is 2 with a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 802.0
If we take 42 away from 50, we end up with 8.
Grab the next digit (3) from the dividend, add it to 8, then carry on: 83 / 21

Let's proceed to step 6:
If we divide 83 by 21, we get 3 and a remainder of 20.
Use 3 as the next digit of our solution. 
Result so far: 8023.0
If we subtract 63 from 83, we 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.

Going ahead to step 7:
The number 21 fits into 200 9 times, leaving a remainder of 11.
The next digit of our result is 9. 
Result so far: 8023.9
Subtracting 189 from 200 leaves us 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.

Going ahead to step 8:
21 goes into 110 5 times with a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 8023.95
Subtract 105 from 110 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 9:
21 can be fit into 50 2 times, resulting in a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 8023.952
Subtract 42 from 50 to get 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 10:
21 goes into 80 3 times with a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 8023.9523
Subtract 63 from 80 to get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 11:
21 goes into 170 8 times with a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 8023.95238
If we subtract 168 from 170, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 12:
20 divided by 21 is 0 with a remainder of 20.
The next digit of our result is 0. 
Result so far: 8023.95238
If we take 0 away from 20, we end up with 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 13:
200 divided by 21 is 9 with a remainder of 11.
Put 9 as the next digit of the answer. 
Result so far: 8023.9523809
Subtracting 189 from 200 leaves us 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.

Moving on to step 14:
When dividing 110 by 21, we get 5 with a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 8023.95238095
The remainder is 5 after subtracting 105 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

After the division, we end up with 8023.95238095 and a remainder of 5e-09.