We divide 21210 by 31
We want to figure out the number of times 21210 can be divided by 31.

On to step 1:
31 goes into 2 0 times with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 31

Moving on to step 2:
21 divided by 31 is 0 with a remainder of 21.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 21 after subtracting 0 from 21.
Grab the next digit (2) from the dividend, add it to 21, then carry on: 212 / 31

Let's proceed to step 3:
31 goes into 212 6 times with a remainder of 26.
Use 6 as the next digit of our solution. 
Result so far: 6.0
The remainder is 26 after subtracting 186 from 212.
Take the next digit (1) from the dividend and append it to 26, then repeat: 261 / 31

Let's proceed to step 4:
The number 31 fits into 261 8 times, leaving a remainder of 13.
Record the quotient 8 as the next digit in the result. 
Result so far: 68.0
Subtracting 248 from 261 leaves us with 13.
Include the next digit (0) from the dividend after 13, then repeat: 130 / 31

Let's proceed to step 5:
When dividing 130 by 31, we get 4 with a remainder of 6.
Put 4 as the next digit of the answer. 
Result so far: 684.0
Deduct 124 from 130 and we're left 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.

Advancing to step 6:
If we divide 60 by 31, we get 1 and a remainder of 29.
Record the quotient 1 as the next digit in the result. 
Result so far: 684.1
If we take 31 away from 60, we end up with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

On to step 7:
When dividing 290 by 31, we get 9 with a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 684.19
The remainder is 11 after subtracting 279 from 290.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Step 8:
If we divide 110 by 31, we get 3 and a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 684.193
Subtract 93 from 110 to get 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 9:
The number 31 fits into 170 5 times, leaving a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 684.1935
The remainder is 15 after subtracting 155 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 10:
When dividing 150 by 31, we get 4 with a remainder of 26.
Use 4 as the next digit of our solution. 
Result so far: 684.19354
If we subtract 124 from 150, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Step 11:
If we divide 260 by 31, we get 8 and a remainder of 12.
The next digit of our result is 8. 
Result so far: 684.193548
Subtract 248 from 260 to 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.

Moving on to step 12:
The number 31 fits into 120 3 times, leaving a remainder of 27.
The number 3 becomes the next digit in our result. 
Result so far: 684.1935483
Deduct 93 from 120 and we're left with 27.
Since there are no more digits in the dividend, we add a zero to the remainder making it 270, and continue the process.

Step 13:
If we divide 270 by 31, we get 8 and a remainder of 22.
The number 8 becomes the next digit in our result. 
Result so far: 684.19354838
The remainder is 22 after subtracting 248 from 270.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

The quotient of the division is 684.19354838, and the remainder is 2.2e-08.