Let's divide 390485 by 87
We're looking to find how many times 87 goes into 390485.

Advancing to step 1:
87 goes into 3 0 times with a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 87

Advancing to step 2:
39 divided by 87 is 0 with a remainder of 39.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 39 and we're left with 39.
Append the next digit (0) from the dividend to 39 and continue with: 390 / 87

Let's proceed to step 3:
If we divide 390 by 87, we get 4 and a remainder of 42.
Record the quotient 4 as the next digit in the result. 
Result so far: 4.0
If we take 348 away from 390, we end up with 42.
Append the next digit (4) from the dividend to 42 and continue with: 424 / 87

Let's proceed to step 4:
87 can be fit into 424 4 times, resulting in a remainder of 76.
Write down 4 as next digit of the result. 
Result so far: 44.0
Deduct 348 from 424 and we're left with 76.
Append the next digit (8) from the dividend to 76 and continue with: 768 / 87

Step 5:
The number 87 fits into 768 8 times, leaving a remainder of 72.
Put 8 as the next digit of the answer. 
Result so far: 448.0
Subtracting 696 from 768 leaves us with 72.
Take the next digit (5) from the dividend and append it to 72, then repeat: 725 / 87

On to step 6:
87 goes into 725 8 times with a remainder of 29.
The number 8 becomes the next digit in our result. 
Result so far: 4488.0
Subtracting 696 from 725 leaves us with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Advancing to step 7:
The number 87 fits into 290 3 times, leaving a remainder of 29.
The number 3 becomes the next digit in our result. 
Result so far: 4488.3
Subtracting 261 from 290 leaves us with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Advancing to step 8:
87 can be fit into 290 3 times, resulting in a remainder of 29.
The next digit of our result is 3. 
Result so far: 4488.33
Subtracting 261 from 290 leaves us with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Our division results in 4488.33 with a remaining 0.029.