We look at the division of 879399 by 81 
Let's see how many times 81 fits into 879399.

On to step 1:
If we divide 8 by 81, we get 0 and a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Append the next digit (7) from the dividend to 8 and continue with: 87 / 81

Step 2:
The number 81 fits into 87 1 times, leaving a remainder of 6.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we subtract 81 from 87, we get 6.
Take the next digit (9) from the dividend and append it to 6, then repeat: 69 / 81

On to step 3:
69 divided by 81 is 0 with a remainder of 69.
Use 0 as the next digit of our solution. 
Result so far: 10.0
The remainder is 69 after subtracting 0 from 69.
Include the next digit (3) from the dividend after 69, then repeat: 693 / 81

Let's proceed to step 4:
693 divided by 81 is 8 with a remainder of 45.
Write down 8 as next digit of the result. 
Result so far: 108.0
If we take 648 away from 693, we end up with 45.
Include the next digit (9) from the dividend after 45, then repeat: 459 / 81

Let's proceed to step 5:
The number 81 fits into 459 5 times, leaving a remainder of 54.
The number 5 becomes the next digit in our result. 
Result so far: 1085.0
The remainder is 54 after subtracting 405 from 459.
Take the next digit (9) from the dividend and append it to 54, then repeat: 549 / 81

On to step 6:
If we divide 549 by 81, we get 6 and a remainder of 63.
Write down 6 as next digit of the result. 
Result so far: 10856.0
Deduct 486 from 549 and we're left with 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

Advancing to step 7:
81 can be fit into 630 7 times, resulting in a remainder of 63.
Record the quotient 7 as the next digit in the result. 
Result so far: 10856.7
Deduct 567 from 630 and we're left with 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

Step 8:
81 goes into 630 7 times with a remainder of 63.
The next digit of our result is 7. 
Result so far: 10856.77
Subtract 567 from 630 to get 63.
Since there are no more digits in the dividend, we add a zero to the remainder making it 630, and continue the process.

The quotient of the division is 10856.77, and the remainder is 0.063.