We divide 393512 by 90
We want to divide 393512 by 90.

Step 1:
When dividing 3 by 90, we get 0 with a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Take the next digit (9) from the dividend and append it to 3, then repeat: 39 / 90

Advancing to step 2:
90 can be fit into 39 0 times, resulting in a remainder of 39.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 39 to get 39.
Fetch the next digit (3) from the dividend, attach it to 39 and continue: 393 / 90

Step 3:
90 can be fit into 393 4 times, resulting in a remainder of 33.
The next digit of our result is 4. 
Result so far: 4.0
Subtract 360 from 393 to get 33.
Grab the next digit (5) from the dividend, add it to 33, then carry on: 335 / 90

Step 4:
90 goes into 335 3 times with a remainder of 65.
Record the quotient 3 as the next digit in the result. 
Result so far: 43.0
If we subtract 270 from 335, we get 65.
Grab the next digit (1) from the dividend, add it to 65, then carry on: 651 / 90

Let's proceed to step 5:
90 goes into 651 7 times with a remainder of 21.
Write down 7 as next digit of the result. 
Result so far: 437.0
Deduct 630 from 651 and we're left with 21.
Take the next digit (2) from the dividend and append it to 21, then repeat: 212 / 90

Step 6:
90 goes into 212 2 times with a remainder of 32.
Write down 2 as next digit of the result. 
Result so far: 4372.0
Subtract 180 from 212 to get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Let's proceed to step 7:
90 can be fit into 320 3 times, resulting in a remainder of 50.
Use 3 as the next digit of our solution. 
Result so far: 4372.3
Subtract 270 from 320 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Moving on to step 8:
500 divided by 90 is 5 with a remainder of 50.
The next digit of our result is 5. 
Result so far: 4372.35
If we take 450 away from 500, we end up with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Moving on to step 9:
When dividing 500 by 90, we get 5 with a remainder of 50.
Use 5 as the next digit of our solution. 
Result so far: 4372.355
Deduct 450 from 500 and we're left with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

The final outcome is 4372.355, with a leftover of 0.005.