143903 divided by 21 
We want to divide 143903 by 21.

Let's proceed to step 1:
When dividing 1 by 21, we get 0 with a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Include the next digit (4) from the dividend after 1, then repeat: 14 / 21

On to step 2:
21 can be fit into 14 0 times, resulting in a remainder of 14.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 14 after subtracting 0 from 14.
Fetch the next digit (3) from the dividend, attach it to 14 and continue: 143 / 21

Advancing to step 3:
When dividing 143 by 21, we get 6 with a remainder of 17.
Record the quotient 6 as the next digit in the result. 
Result so far: 6.0
Subtracting 126 from 143 leaves us with 17.
Grab the next digit (9) from the dividend, add it to 17, then carry on: 179 / 21

Let's proceed to step 4:
The number 21 fits into 179 8 times, leaving a remainder of 11.
Write down 8 as next digit of the result. 
Result so far: 68.0
If we take 168 away from 179, we end up with 11.
Bring next digit (0) of the dividend behind the 11 and repeat the process: 110 / 21

Advancing to step 5:
When dividing 110 by 21, we get 5 with a remainder of 5.
The number 5 becomes the next digit in our result. 
Result so far: 685.0
Subtract 105 from 110 to get 5.
Fetch the next digit (3) from the dividend, attach it to 5 and continue: 53 / 21

Moving on to step 6:
21 goes into 53 2 times with a remainder of 11.
Record the quotient 2 as the next digit in the result. 
Result so far: 6852.0
If we subtract 42 from 53, we get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

On to step 7:
110 divided by 21 is 5 with a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 6852.5
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.

Let's proceed to step 8:
If we divide 50 by 21, we get 2 and a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 6852.52
The remainder is 8 after subtracting 42 from 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 9:
21 can be fit into 80 3 times, resulting in a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 6852.523
If we subtract 63 from 80, we 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.

Advancing to step 10:
21 can be fit into 170 8 times, resulting in a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 6852.5238
Deduct 168 from 170 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Let's proceed to step 11:
If we divide 20 by 21, we get 0 and a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 6852.5238
Subtracting 0 from 20 leaves us 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.

Going ahead to step 12:
21 can be fit into 200 9 times, resulting in a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 6852.523809
Subtract 189 from 200 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Step 13:
If we divide 110 by 21, we get 5 and a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 6852.5238095
Subtracting 105 from 110 leaves us with 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 14:
21 can be fit into 50 2 times, resulting in a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 6852.52380952
If we take 42 away from 50, we end up with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

The quotient of the division is 6852.52380952, and the remainder is 8e-09.