478383 ÷ 21 
We're looking to find how many times 21 goes into 478383.

On to step 1:
21 goes into 4 0 times with a remainder of 4.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Include the next digit (7) from the dividend after 4, then repeat: 47 / 21

Let's proceed to step 2:
21 can be fit into 47 2 times, resulting in a remainder of 5.
The next digit of our result is 2. 
Result so far: 2.0
If we take 42 away from 47, we end up with 5.
Include the next digit (8) from the dividend after 5, then repeat: 58 / 21

Going ahead to step 3:
The number 21 fits into 58 2 times, leaving a remainder of 16.
The number 2 becomes the next digit in our result. 
Result so far: 22.0
Deduct 42 from 58 and we're left with 16.
Grab the next digit (3) from the dividend, add it to 16, then carry on: 163 / 21

Going ahead to step 4:
163 divided by 21 is 7 with a remainder of 16.
Use 7 as the next digit of our solution. 
Result so far: 227.0
If we subtract 147 from 163, we get 16.
Fetch the next digit (8) from the dividend, attach it to 16 and continue: 168 / 21

Going ahead to step 5:
If we divide 168 by 21, we get 8 and a remainder of 0.
The next digit of our result is 8. 
Result so far: 2278.0
If we take 168 away from 168, we end up with 0.
Grab the next digit (3) from the dividend, add it to 0, then carry on: 3 / 21

Moving on to step 6:
21 can be fit into 3 0 times, resulting in a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 22780.0
The remainder is 3 after subtracting 0 from 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 7:
When dividing 30 by 21, we get 1 with a remainder of 9.
The next digit of our result is 1. 
Result so far: 22780.1
Deduct 21 from 30 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Going ahead to step 8:
90 divided by 21 is 4 with a remainder of 6.
Record the quotient 4 as the next digit in the result. 
Result so far: 22780.14
The remainder is 6 after subtracting 84 from 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 9:
If we divide 60 by 21, we get 2 and a remainder of 18.
Use 2 as the next digit of our solution. 
Result so far: 22780.142
Deduct 42 from 60 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 10:
21 goes into 180 8 times with a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 22780.1428
The remainder is 12 after subtracting 168 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 11:
If we divide 120 by 21, we get 5 and a remainder of 15.
Put 5 as the next digit of the answer. 
Result so far: 22780.14285
Subtract 105 from 120 to get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 12:
150 divided by 21 is 7 with a remainder of 3.
Put 7 as the next digit of the answer. 
Result so far: 22780.142857
If we subtract 147 from 150, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Step 13:
21 can be fit into 30 1 times, resulting in a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 22780.1428571
Deduct 21 from 30 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 14:
90 divided by 21 is 4 with a remainder of 6.
The next digit of our result is 4. 
Result so far: 22780.14285714
If we take 84 away from 90, we end up with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Our division results in 22780.14285714 with a remaining 6e-09.