358310 divided by 21 
Let's see how many times 21 fits into 358310.

Going ahead to step 1:
If we divide 3 by 21, we get 0 and a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 3 after subtracting 0 from 3.
Grab the next digit (5) from the dividend, add it to 3, then carry on: 35 / 21

Advancing to step 2:
When dividing 35 by 21, we get 1 with a remainder of 14.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtracting 21 from 35 leaves us with 14.
Include the next digit (8) from the dividend after 14, then repeat: 148 / 21

Let's proceed to step 3:
21 can be fit into 148 7 times, resulting in a remainder of 1.
Put 7 as the next digit of the answer. 
Result so far: 17.0
Subtracting 147 from 148 leaves us with 1.
Append the next digit (3) from the dividend to 1 and continue with: 13 / 21

Going ahead to step 4:
When dividing 13 by 21, we get 0 with a remainder of 13.
Use 0 as the next digit of our solution. 
Result so far: 170.0
Deduct 0 from 13 and we're left with 13.
Bring next digit (1) of the dividend behind the 13 and repeat the process: 131 / 21

Step 5:
When dividing 131 by 21, we get 6 with a remainder of 5.
The number 6 becomes the next digit in our result. 
Result so far: 1706.0
If we subtract 126 from 131, we get 5.
Include the next digit (0) from the dividend after 5, then repeat: 50 / 21

Going ahead to step 6:
The number 21 fits into 50 2 times, leaving a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 17062.0
Subtracting 42 from 50 leaves us 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.

Moving on to step 7:
The number 21 fits into 80 3 times, leaving a remainder of 17.
Put 3 as the next digit of the answer. 
Result so far: 17062.3
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.

Let's proceed to step 8:
If we divide 170 by 21, we get 8 and a remainder of 2.
The next digit of our result is 8. 
Result so far: 17062.38
If we take 168 away from 170, 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.

Step 9:
When dividing 20 by 21, we get 0 with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 17062.38
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.

Advancing to step 10:
21 goes into 200 9 times with a remainder of 11.
The next digit of our result is 9. 
Result so far: 17062.3809
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.

Advancing to step 11:
21 can be fit into 110 5 times, resulting in a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 17062.38095
If we take 105 away from 110, we end up 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.

On to step 12:
When dividing 50 by 21, we get 2 with a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 17062.380952
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.

Moving on to step 13:
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: 17062.3809523
The remainder is 17 after subtracting 63 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 14:
When dividing 170 by 21, we get 8 with a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 17062.38095238
Subtract 168 from 170 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

In conclusion, the division gives 17062.38095238 with a balance of 2e-09.