We look at the division of 785148 by 21 
Let's see how many times 21 fits into 785148.

Going ahead to step 1:
If we divide 7 by 21, we get 0 and a remainder of 7.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 7 and we're left with 7.
Append the next digit (8) from the dividend to 7 and continue with: 78 / 21

Step 2:
21 goes into 78 3 times with a remainder of 15.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
Deduct 63 from 78 and we're left with 15.
Fetch the next digit (5) from the dividend, attach it to 15 and continue: 155 / 21

On to step 3:
The number 21 fits into 155 7 times, leaving a remainder of 8.
Use 7 as the next digit of our solution. 
Result so far: 37.0
Subtracting 147 from 155 leaves us with 8.
Append the next digit (1) from the dividend to 8 and continue with: 81 / 21

Advancing to step 4:
21 goes into 81 3 times with a remainder of 18.
The next digit of our result is 3. 
Result so far: 373.0
If we subtract 63 from 81, we get 18.
Fetch the next digit (4) from the dividend, attach it to 18 and continue: 184 / 21

On to step 5:
21 goes into 184 8 times with a remainder of 16.
Write down 8 as next digit of the result. 
Result so far: 3738.0
If we take 168 away from 184, we end up with 16.
Bring next digit (8) of the dividend behind the 16 and repeat the process: 168 / 21

Going ahead to step 6:
21 goes into 168 8 times with a remainder of 0.
Write down 8 as next digit of the result. 
Result so far: 37388.0
Subtracting 168 from 168 leaves us 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.

Advancing to step 7:
21 can be fit into 0 0 times, resulting in a remainder of 0.
The next digit of our result is 0. 
Result so far: 37388.0
Deduct 0 from 0 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.

Advancing to step 8:
21 goes into 0 0 times with a remainder of 0.
The next digit of our result is 0. 
Result so far: 37388.0
Deduct 0 from 0 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 37388.0, and the remainder is 0.0.