We look at the division of 31001511 by 21 
We're looking to find how many times 21 goes into 31001511.

Let's proceed 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
If we take 0 away from 3, we end up with 3.
Grab the next digit (1) from the dividend, add it to 3, then carry on: 31 / 21

Moving on to step 2:
21 can be fit into 31 1 times, resulting in a remainder of 10.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 21 away from 31, we end up with 10.
Append the next digit (0) from the dividend to 10 and continue with: 100 / 21

Going ahead to step 3:
If we divide 100 by 21, we get 4 and a remainder of 16.
Write down 4 as next digit of the result. 
Result so far: 14.0
Subtracting 84 from 100 leaves us with 16.
Take the next digit (0) from the dividend and append it to 16, then repeat: 160 / 21

On to step 4:
The number 21 fits into 160 7 times, leaving a remainder of 13.
The next digit of our result is 7. 
Result so far: 147.0
Deduct 147 from 160 and we're left with 13.
Append the next digit (1) from the dividend to 13 and continue with: 131 / 21

Advancing to step 5:
131 divided by 21 is 6 with a remainder of 5.
Use 6 as the next digit of our solution. 
Result so far: 1476.0
Deduct 126 from 131 and we're left with 5.
Grab the next digit (5) from the dividend, add it to 5, then carry on: 55 / 21

Moving on to step 6:
21 can be fit into 55 2 times, resulting in a remainder of 13.
Put 2 as the next digit of the answer. 
Result so far: 14762.0
The remainder is 13 after subtracting 42 from 55.
Append the next digit (1) from the dividend to 13 and continue with: 131 / 21

Let's proceed to step 7:
If we divide 131 by 21, we get 6 and a remainder of 5.
Use 6 as the next digit of our solution. 
Result so far: 147626.0
Subtract 126 from 131 to get 5.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 21

Going ahead to step 8:
21 goes into 51 2 times with a remainder of 9.
The number 2 becomes the next digit in our result. 
Result so far: 1476262.0
If we take 42 away from 51, we end up 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.

On to step 9:
21 goes into 90 4 times with a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 1476262.4
Subtracting 84 from 90 leaves us 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.

Going ahead to step 10:
21 can be fit into 60 2 times, resulting in a remainder of 18.
Write down 2 as next digit of the result. 
Result so far: 1476262.42
If we subtract 42 from 60, we 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.

Let's proceed to step 11:
180 divided by 21 is 8 with a remainder of 12.
Record the quotient 8 as the next digit in the result. 
Result so far: 1476262.428
The remainder is 12 after subtracting 168 from 180.
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 21 fits into 120 5 times, leaving a remainder of 15.
Put 5 as the next digit of the answer. 
Result so far: 1476262.4285
Deduct 105 from 120 and we're left 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.

Advancing to step 13:
150 divided by 21 is 7 with a remainder of 3.
The next digit of our result is 7. 
Result so far: 1476262.42857
If we subtract 147 from 150, we 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.

Let's proceed to step 14:
The number 21 fits into 30 1 times, leaving a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 1476262.428571
If we subtract 21 from 30, we get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 15:
21 goes into 90 4 times with a remainder of 6.
The next digit of our result is 4. 
Result so far: 1476262.4285714
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.

Advancing to step 16:
When dividing 60 by 21, we get 2 with a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 1476262.42857142
If we subtract 42 from 60, we 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 quotient of the division is 1476262.42857142, and the remainder is 1.8e-08.