We look at the division of 165751 by 21 
Let's see how many times 21 fits into 165751.

Going ahead to step 1:
When dividing 1 by 21, we get 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Take the next digit (6) from the dividend and append it to 1, then repeat: 16 / 21

Going ahead to step 2:
If we divide 16 by 21, we get 0 and a remainder of 16.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 16 to get 16.
Bring next digit (5) of the dividend behind the 16 and repeat the process: 165 / 21

On to step 3:
165 divided by 21 is 7 with a remainder of 18.
Use 7 as the next digit of our solution. 
Result so far: 7.0
The remainder is 18 after subtracting 147 from 165.
Append the next digit (7) from the dividend to 18 and continue with: 187 / 21

Step 4:
21 goes into 187 8 times with a remainder of 19.
Put 8 as the next digit of the answer. 
Result so far: 78.0
If we take 168 away from 187, we end up with 19.
Grab the next digit (5) from the dividend, add it to 19, then carry on: 195 / 21

Step 5:
If we divide 195 by 21, we get 9 and a remainder of 6.
Write down 9 as next digit of the result. 
Result so far: 789.0
Deduct 189 from 195 and we're left with 6.
Bring next digit (1) of the dividend behind the 6 and repeat the process: 61 / 21

Step 6:
If we divide 61 by 21, we get 2 and a remainder of 19.
Record the quotient 2 as the next digit in the result. 
Result so far: 7892.0
If we take 42 away from 61, we end up with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Step 7:
21 goes into 190 9 times with a remainder of 1.
Use 9 as the next digit of our solution. 
Result so far: 7892.9
The remainder is 1 after subtracting 189 from 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 8:
When dividing 10 by 21, we get 0 with a remainder of 10.
The next digit of our result is 0. 
Result so far: 7892.9
Subtract 0 from 10 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 9:
When dividing 100 by 21, we get 4 with a remainder of 16.
Write down 4 as next digit of the result. 
Result so far: 7892.904
Subtract 84 from 100 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Going ahead to step 10:
When dividing 160 by 21, we get 7 with a remainder of 13.
Use 7 as the next digit of our solution. 
Result so far: 7892.9047
If we take 147 away from 160, we end up with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Moving on to step 11:
21 can be fit into 130 6 times, resulting in a remainder of 4.
The next digit of our result is 6. 
Result so far: 7892.90476
The remainder is 4 after subtracting 126 from 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 12:
40 divided by 21 is 1 with a remainder of 19.
Record the quotient 1 as the next digit in the result. 
Result so far: 7892.904761
The remainder is 19 after subtracting 21 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 13:
If we divide 190 by 21, we get 9 and a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 7892.9047619
Subtract 189 from 190 to get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Advancing to step 14:
21 goes into 10 0 times with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 7892.9047619
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final result is 7892.9047619 with a remainder of 1e-08.