We look at the division of 78924239 by 90 
We're looking to find how many times 90 goes into 78924239.

Step 1:
7 divided by 90 is 0 with a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 7, we end up with 7.
Bring next digit (8) of the dividend behind the 7 and repeat the process: 78 / 90

On to step 2:
If we divide 78 by 90, we get 0 and a remainder of 78.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 78 to get 78.
Grab the next digit (9) from the dividend, add it to 78, then carry on: 789 / 90

Let's proceed to step 3:
90 goes into 789 8 times with a remainder of 69.
Record the quotient 8 as the next digit in the result. 
Result so far: 8.0
Deduct 720 from 789 and we're left with 69.
Fetch the next digit (2) from the dividend, attach it to 69 and continue: 692 / 90

Step 4:
When dividing 692 by 90, we get 7 with a remainder of 62.
Record the quotient 7 as the next digit in the result. 
Result so far: 87.0
Subtract 630 from 692 to get 62.
Grab the next digit (4) from the dividend, add it to 62, then carry on: 624 / 90

On to step 5:
If we divide 624 by 90, we get 6 and a remainder of 84.
The next digit of our result is 6. 
Result so far: 876.0
Subtract 540 from 624 to get 84.
Append the next digit (2) from the dividend to 84 and continue with: 842 / 90

Moving on to step 6:
842 divided by 90 is 9 with a remainder of 32.
The next digit of our result is 9. 
Result so far: 8769.0
If we take 810 away from 842, we end up with 32.
Grab the next digit (3) from the dividend, add it to 32, then carry on: 323 / 90

Advancing to step 7:
323 divided by 90 is 3 with a remainder of 53.
Use 3 as the next digit of our solution. 
Result so far: 87693.0
Subtracting 270 from 323 leaves us with 53.
Fetch the next digit (9) from the dividend, attach it to 53 and continue: 539 / 90

Moving on to step 8:
When dividing 539 by 90, we get 5 with a remainder of 89.
Record the quotient 5 as the next digit in the result. 
Result so far: 876935.0
Deduct 450 from 539 and we're left with 89.
Since there are no more digits in the dividend, we add a zero to the remainder making it 890, and continue the process.

Step 9:
The number 90 fits into 890 9 times, leaving a remainder of 80.
Record the quotient 9 as the next digit in the result. 
Result so far: 876935.9
The remainder is 80 after subtracting 810 from 890.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Advancing to step 10:
The number 90 fits into 800 8 times, leaving a remainder of 80.
Write down 8 as next digit of the result. 
Result so far: 876935.98
The remainder is 80 after subtracting 720 from 800.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Advancing to step 11:
If we divide 800 by 90, we get 8 and a remainder of 80.
Use 8 as the next digit of our solution. 
Result so far: 876935.988
If we subtract 720 from 800, we get 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

The final result is 876935.988 with a remainder of 0.008.