337708 divided by 21 
Our goal is to divide 337708 by 21.

Moving on to step 1:
If we divide 3 by 21, we get 0 and a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Bring next digit (3) of the dividend behind the 3 and repeat the process: 33 / 21

Moving on to step 2:
21 goes into 33 1 times with a remainder of 12.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Deduct 21 from 33 and we're left with 12.
Include the next digit (7) from the dividend after 12, then repeat: 127 / 21

Let's proceed to step 3:
21 can be fit into 127 6 times, resulting in a remainder of 1.
The next digit of our result is 6. 
Result so far: 16.0
If we take 126 away from 127, we end up with 1.
Fetch the next digit (7) from the dividend, attach it to 1 and continue: 17 / 21

On to step 4:
When dividing 17 by 21, we get 0 with a remainder of 17.
The number 0 becomes the next digit in our result. 
Result so far: 160.0
The remainder is 17 after subtracting 0 from 17.
Bring next digit (0) of the dividend behind the 17 and repeat the process: 170 / 21

On to step 5:
The number 21 fits into 170 8 times, leaving a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 1608.0
Subtract 168 from 170 to get 2.
Append the next digit (8) from the dividend to 2 and continue with: 28 / 21

On to step 6:
28 divided by 21 is 1 with a remainder of 7.
Put 1 as the next digit of the answer. 
Result so far: 16081.0
If we subtract 21 from 28, we get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Moving on to step 7:
21 goes into 70 3 times with a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 16081.3
The remainder is 7 after subtracting 63 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Let's proceed to step 8:
The number 21 fits into 70 3 times, leaving a remainder of 7.
Record the quotient 3 as the next digit in the result. 
Result so far: 16081.33
Deduct 63 from 70 and we're left with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

The final outcome is 16081.33, with a leftover of 0.007.