957210 ÷ 21 
Let's see how many times 21 fits into 957210.

Going ahead to step 1:
If we divide 9 by 21, we get 0 and a remainder of 9.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 9, we get 9.
Include the next digit (5) from the dividend after 9, then repeat: 95 / 21

Advancing to step 2:
When dividing 95 by 21, we get 4 with a remainder of 11.
Write down 4 as next digit of the result. 
Result so far: 4.0
The remainder is 11 after subtracting 84 from 95.
Grab the next digit (7) from the dividend, add it to 11, then carry on: 117 / 21

Moving on to step 3:
117 divided by 21 is 5 with a remainder of 12.
The number 5 becomes the next digit in our result. 
Result so far: 45.0
If we subtract 105 from 117, we get 12.
Fetch the next digit (2) from the dividend, attach it to 12 and continue: 122 / 21

Advancing to step 4:
21 can be fit into 122 5 times, resulting in a remainder of 17.
Use 5 as the next digit of our solution. 
Result so far: 455.0
The remainder is 17 after subtracting 105 from 122.
Grab the next digit (1) from the dividend, add it to 17, then carry on: 171 / 21

Going ahead to step 5:
The number 21 fits into 171 8 times, leaving a remainder of 3.
The number 8 becomes the next digit in our result. 
Result so far: 4558.0
If we take 168 away from 171, we end up with 3.
Take the next digit (0) from the dividend and append it to 3, then repeat: 30 / 21

Step 6:
When dividing 30 by 21, we get 1 with a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 45581.0
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.

Advancing to step 7:
90 divided by 21 is 4 with a remainder of 6.
The next digit of our result is 4. 
Result so far: 45581.4
If we subtract 84 from 90, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Advancing to step 8:
60 divided by 21 is 2 with a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 45581.42
Subtracting 42 from 60 leaves us 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.

Let's proceed to step 9:
The number 21 fits into 180 8 times, leaving a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 45581.428
If we subtract 168 from 180, we get 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 10:
21 can be fit into 120 5 times, resulting in a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 45581.4285
Subtracting 105 from 120 leaves us with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 11:
If we divide 150 by 21, we get 7 and a remainder of 3.
The next digit of our result is 7. 
Result so far: 45581.42857
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.

Step 12:
21 goes into 30 1 times with a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 45581.428571
The remainder is 9 after subtracting 21 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

On to step 13:
21 can be fit into 90 4 times, resulting in a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 45581.4285714
If we subtract 84 from 90, we get 6.
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 14:
21 goes into 60 2 times with a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 45581.42857142
Subtract 42 from 60 to get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

The final outcome is 45581.42857142, with a leftover of 1.8e-08.