Let's divide 78015 by 42
We're looking to find how many times 42 goes into 78015.

On to step 1:
If we divide 7 by 42, we get 0 and a remainder of 7.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Take the next digit (8) from the dividend and append it to 7, then repeat: 78 / 42

Going ahead to step 2:
78 divided by 42 is 1 with a remainder of 36.
Put 1 as the next digit of the answer. 
Result so far: 1.0
The remainder is 36 after subtracting 42 from 78.
Append the next digit (0) from the dividend to 36 and continue with: 360 / 42

Moving on to step 3:
42 can be fit into 360 8 times, resulting in a remainder of 24.
Use 8 as the next digit of our solution. 
Result so far: 18.0
Subtract 336 from 360 to get 24.
Append the next digit (1) from the dividend to 24 and continue with: 241 / 42

Step 4:
42 can be fit into 241 5 times, resulting in a remainder of 31.
The next digit of our result is 5. 
Result so far: 185.0
Subtract 210 from 241 to get 31.
Append the next digit (5) from the dividend to 31 and continue with: 315 / 42

Advancing to step 5:
If we divide 315 by 42, we get 7 and a remainder of 21.
The next digit of our result is 7. 
Result so far: 1857.0
If we take 294 away from 315, we end up with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

On to step 6:
42 goes into 210 5 times with a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 1857.5
If we subtract 210 from 210, we 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.

Let's proceed to step 7:
42 goes into 0 0 times with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 1857.5
Deduct 0 from 0 and we're left 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.

Advancing to step 8:
42 goes into 0 0 times with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 1857.5
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.

The final outcome is 1857.5, with a leftover of 0.0.