We're dividing 42087 by 12 
Let's see how many times 12 fits into 42087.

Advancing to step 1:
If we divide 4 by 12, we get 0 and a remainder of 4.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 4 leaves us with 4.
Append the next digit (2) from the dividend to 4 and continue with: 42 / 12

Moving on to step 2:
42 divided by 12 is 3 with a remainder of 6.
Write down 3 as next digit of the result. 
Result so far: 3.0
The remainder is 6 after subtracting 36 from 42.
Fetch the next digit (0) from the dividend, attach it to 6 and continue: 60 / 12

Advancing to step 3:
60 divided by 12 is 5 with a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 35.0
Subtracting 60 from 60 leaves us with 0.
Fetch the next digit (8) from the dividend, attach it to 0 and continue: 8 / 12

Let's proceed to step 4:
12 goes into 8 0 times with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 350.0
Subtracting 0 from 8 leaves us with 8.
Take the next digit (7) from the dividend and append it to 8, then repeat: 87 / 12

Moving on to step 5:
12 can be fit into 87 7 times, resulting in a remainder of 3.
The next digit of our result is 7. 
Result so far: 3507.0
Deduct 84 from 87 and we're left with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Going ahead to step 6:
When dividing 30 by 12, we get 2 with a remainder of 6.
Put 2 as the next digit of the answer. 
Result so far: 3507.2
If we subtract 24 from 30, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 7:
If we divide 60 by 12, we get 5 and a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 3507.25
Subtracting 60 from 60 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
0 divided by 12 is 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 3507.25
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 9:
If we divide 0 by 12, we get 0 and a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 3507.25
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Our division results in 3507.25 with a remaining 0.0.