307413 ÷ 21 
Let's see how many times 21 fits into 307413.

On to step 1:
21 goes into 3 0 times with a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Include the next digit (0) from the dividend after 3, then repeat: 30 / 21

Let's proceed to step 2:
21 goes into 30 1 times with a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtracting 21 from 30 leaves us with 9.
Include the next digit (7) from the dividend after 9, then repeat: 97 / 21

Let's proceed to step 3:
If we divide 97 by 21, we get 4 and a remainder of 13.
Record the quotient 4 as the next digit in the result. 
Result so far: 14.0
Subtract 84 from 97 to get 13.
Grab the next digit (4) from the dividend, add it to 13, then carry on: 134 / 21

Step 4:
The number 21 fits into 134 6 times, leaving a remainder of 8.
The number 6 becomes the next digit in our result. 
Result so far: 146.0
The remainder is 8 after subtracting 126 from 134.
Take the next digit (1) from the dividend and append it to 8, then repeat: 81 / 21

Advancing to step 5:
When dividing 81 by 21, we get 3 with a remainder of 18.
Write down 3 as next digit of the result. 
Result so far: 1463.0
If we subtract 63 from 81, we get 18.
Append the next digit (3) from the dividend to 18 and continue with: 183 / 21

On to step 6:
183 divided by 21 is 8 with a remainder of 15.
The next digit of our result is 8. 
Result so far: 14638.0
The remainder is 15 after subtracting 168 from 183.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Advancing to step 7:
150 divided by 21 is 7 with a remainder of 3.
The number 7 becomes the next digit in our result. 
Result so far: 14638.7
Subtract 147 from 150 to 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.

Going ahead to step 8:
When dividing 30 by 21, we get 1 with a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 14638.71
Subtract 21 from 30 to get 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 9:
If we divide 90 by 21, we get 4 and a remainder of 6.
The next digit of our result is 4. 
Result so far: 14638.714
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.

Going ahead to step 10:
60 divided by 21 is 2 with a remainder of 18.
Write down 2 as next digit of the result. 
Result so far: 14638.7142
If we take 42 away from 60, we end up 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.

On to step 11:
180 divided by 21 is 8 with a remainder of 12.
The next digit of our result is 8. 
Result so far: 14638.71428
If we take 168 away from 180, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 12:
If we divide 120 by 21, we get 5 and a remainder of 15.
The next digit of our result is 5. 
Result so far: 14638.714285
The remainder is 15 after subtracting 105 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Let's proceed to step 13:
150 divided by 21 is 7 with a remainder of 3.
Use 7 as the next digit of our solution. 
Result so far: 14638.7142857
Deduct 147 from 150 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.

Advancing to step 14:
The number 21 fits into 30 1 times, leaving a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 14638.71428571
Subtracting 21 from 30 leaves us 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.

The final result is 14638.71428571 with a remainder of 9e-09.