We look at the division of 1623 by 90 
Our goal is to divide 1623 by 90.

Step 1:
The number 90 fits into 1 0 times, leaving a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Grab the next digit (6) from the dividend, add it to 1, then carry on: 16 / 90

On to step 2:
16 divided by 90 is 0 with a remainder of 16.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 16 leaves us with 16.
Bring next digit (2) of the dividend behind the 16 and repeat the process: 162 / 90

Moving on to step 3:
If we divide 162 by 90, we get 1 and a remainder of 72.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 90 from 162 to get 72.
Fetch the next digit (3) from the dividend, attach it to 72 and continue: 723 / 90

Going ahead to step 4:
90 goes into 723 8 times with a remainder of 3.
Put 8 as the next digit of the answer. 
Result so far: 18.0
Deduct 720 from 723 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Going ahead to step 5:
30 divided by 90 is 0 with a remainder of 30.
The next digit of our result is 0. 
Result so far: 18.0
If we take 0 away from 30, we end up with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Moving on to step 6:
90 can be fit into 300 3 times, resulting in a remainder of 30.
The number 3 becomes the next digit in our result. 
Result so far: 18.03
Subtracting 270 from 300 leaves us with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Step 7:
300 divided by 90 is 3 with a remainder of 30.
The next digit of our result is 3. 
Result so far: 18.033
Deduct 270 from 300 and we're left with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Our division results in 18.033 with a remaining 0.003.