349505 divided by 21 
Our goal is to divide 349505 by 21.

Step 1:
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: 0.0
Subtracting 0 from 3 leaves us with 3.
Take the next digit (4) from the dividend and append it to 3, then repeat: 34 / 21

On to step 2:
When dividing 34 by 21, we get 1 with a remainder of 13.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we take 21 away from 34, we end up with 13.
Take the next digit (9) from the dividend and append it to 13, then repeat: 139 / 21

Step 3:
When dividing 139 by 21, we get 6 with a remainder of 13.
The number 6 becomes the next digit in our result. 
Result so far: 16.0
Subtract 126 from 139 to get 13.
Include the next digit (5) from the dividend after 13, then repeat: 135 / 21

Going ahead to step 4:
21 can be fit into 135 6 times, resulting in a remainder of 9.
Record the quotient 6 as the next digit in the result. 
Result so far: 166.0
If we take 126 away from 135, we end up with 9.
Fetch the next digit (0) from the dividend, attach it to 9 and continue: 90 / 21

Advancing to step 5:
21 goes into 90 4 times with a remainder of 6.
Record the quotient 4 as the next digit in the result. 
Result so far: 1664.0
Deduct 84 from 90 and we're left with 6.
Grab the next digit (5) from the dividend, add it to 6, then carry on: 65 / 21

Advancing to step 6:
When dividing 65 by 21, we get 3 with a remainder of 2.
Write down 3 as next digit of the result. 
Result so far: 16643.0
If we take 63 away from 65, we end up 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.

Moving on to step 7:
If we divide 20 by 21, we get 0 and a remainder of 20.
The next digit of our result is 0. 
Result so far: 16643.0
If we take 0 away from 20, we end up 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.

Moving on to step 8:
When dividing 200 by 21, we get 9 with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 16643.09
Subtracting 189 from 200 leaves us with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Moving on to step 9:
The number 21 fits into 110 5 times, leaving a remainder of 5.
The next digit of our result is 5. 
Result so far: 16643.095
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.

On to step 10:
21 can be fit into 50 2 times, resulting in a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 16643.0952
If we subtract 42 from 50, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

On to step 11:
21 goes into 80 3 times with a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 16643.09523
If we take 63 away from 80, we end up with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

On to step 12:
21 goes into 170 8 times with a remainder of 2.
The next digit of our result is 8. 
Result so far: 16643.095238
Subtracting 168 from 170 leaves us 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.

Moving on to step 13:
The number 21 fits into 20 0 times, leaving a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 16643.095238
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 14:
When dividing 200 by 21, we get 9 with a remainder of 11.
Put 9 as the next digit of the answer. 
Result so far: 16643.09523809
If we take 189 away from 200, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

The final outcome is 16643.09523809, with a leftover of 1.1e-08.