We're dividing 21521253 by 768 
We want to divide 21521253 by 768.

On to step 1:
768 goes into 2 0 times with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Fetch the next digit (1) from the dividend, attach it to 2 and continue: 21 / 768

Let's proceed to step 2:
When dividing 21 by 768, we get 0 with a remainder of 21.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 21 to get 21.
Include the next digit (5) from the dividend after 21, then repeat: 215 / 768

Going ahead to step 3:
When dividing 215 by 768, we get 0 with a remainder of 215.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 215 after subtracting 0 from 215.
Fetch the next digit (2) from the dividend, attach it to 215 and continue: 2152 / 768

Advancing to step 4:
2152 divided by 768 is 2 with a remainder of 616.
The next digit of our result is 2. 
Result so far: 2.0
The remainder is 616 after subtracting 1536 from 2152.
Bring next digit (1) of the dividend behind the 616 and repeat the process: 6161 / 768

Moving on to step 5:
The number 768 fits into 6161 8 times, leaving a remainder of 17.
Put 8 as the next digit of the answer. 
Result so far: 28.0
If we subtract 6144 from 6161, we get 17.
Bring next digit (2) of the dividend behind the 17 and repeat the process: 172 / 768

Moving on to step 6:
172 divided by 768 is 0 with a remainder of 172.
The number 0 becomes the next digit in our result. 
Result so far: 280.0
If we take 0 away from 172, we end up with 172.
Grab the next digit (5) from the dividend, add it to 172, then carry on: 1725 / 768

Let's proceed to step 7:
The number 768 fits into 1725 2 times, leaving a remainder of 189.
Record the quotient 2 as the next digit in the result. 
Result so far: 2802.0
Deduct 1536 from 1725 and we're left with 189.
Grab the next digit (3) from the dividend, add it to 189, then carry on: 1893 / 768

Let's proceed to step 8:
The number 768 fits into 1893 2 times, leaving a remainder of 357.
Put 2 as the next digit of the answer. 
Result so far: 28022.0
Subtract 1536 from 1893 to get 357.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3570, and continue the process.

Advancing to step 9:
The number 768 fits into 3570 4 times, leaving a remainder of 498.
The next digit of our result is 4. 
Result so far: 28022.4
Subtract 3072 from 3570 to get 498.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4980, and continue the process.

Let's proceed to step 10:
The number 768 fits into 4980 6 times, leaving a remainder of 372.
The number 6 becomes the next digit in our result. 
Result so far: 28022.46
The remainder is 372 after subtracting 4608 from 4980.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3720, and continue the process.

On to step 11:
768 goes into 3720 4 times with a remainder of 648.
Put 4 as the next digit of the answer. 
Result so far: 28022.464
The remainder is 648 after subtracting 3072 from 3720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6480, and continue the process.

Going ahead to step 12:
768 goes into 6480 8 times with a remainder of 336.
The next digit of our result is 8. 
Result so far: 28022.4648
If we subtract 6144 from 6480, we get 336.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3360, and continue the process.

Advancing to step 13:
768 can be fit into 3360 4 times, resulting in a remainder of 288.
The number 4 becomes the next digit in our result. 
Result so far: 28022.46484
The remainder is 288 after subtracting 3072 from 3360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2880, and continue the process.

Let's proceed to step 14:
When dividing 2880 by 768, we get 3 with a remainder of 576.
Record the quotient 3 as the next digit in the result. 
Result so far: 28022.464843
Subtracting 2304 from 2880 leaves us with 576.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5760, and continue the process.

Going ahead to step 15:
5760 divided by 768 is 7 with a remainder of 384.
Record the quotient 7 as the next digit in the result. 
Result so far: 28022.4648437
If we take 5376 away from 5760, we end up with 384.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3840, and continue the process.

Step 16:
768 can be fit into 3840 5 times, resulting in a remainder of 0.
The next digit of our result is 5. 
Result so far: 28022.46484375
Deduct 3840 from 3840 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The quotient of the division is 28022.46484375, and the remainder is 0.0.