We divide 398560 by 90
We're looking to find how many times 90 goes into 398560.

Step 1:
90 goes into 3 0 times with a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Append the next digit (9) from the dividend to 3 and continue with: 39 / 90

Let's proceed to step 2:
90 goes into 39 0 times with a remainder of 39.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 39, we get 39.
Take the next digit (8) from the dividend and append it to 39, then repeat: 398 / 90

Step 3:
398 divided by 90 is 4 with a remainder of 38.
The next digit of our result is 4. 
Result so far: 4.0
Subtract 360 from 398 to get 38.
Fetch the next digit (5) from the dividend, attach it to 38 and continue: 385 / 90

Moving on to step 4:
385 divided by 90 is 4 with a remainder of 25.
The number 4 becomes the next digit in our result. 
Result so far: 44.0
If we subtract 360 from 385, we get 25.
Grab the next digit (6) from the dividend, add it to 25, then carry on: 256 / 90

On to step 5:
The number 90 fits into 256 2 times, leaving a remainder of 76.
Use 2 as the next digit of our solution. 
Result so far: 442.0
Subtract 180 from 256 to get 76.
Bring next digit (0) of the dividend behind the 76 and repeat the process: 760 / 90

Let's proceed to step 6:
The number 90 fits into 760 8 times, leaving a remainder of 40.
Write down 8 as next digit of the result. 
Result so far: 4428.0
The remainder is 40 after subtracting 720 from 760.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Moving on to step 7:
90 goes into 400 4 times with a remainder of 40.
Write down 4 as next digit of the result. 
Result so far: 4428.4
Deduct 360 from 400 and we're left with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 8:
90 goes into 400 4 times with a remainder of 40.
The next digit of our result is 4. 
Result so far: 4428.44
Subtracting 360 from 400 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

After the division, we end up with 4428.44 and a remainder of 0.04.