We can convert the numbers into whole. But remember to move the decimal point same "places" with both the numbers.
To make 0.15 into 15, you need to move the decimal 2 places to the right.
Similarly, you need to move the decimal 2 places to the right, with 0.2 as well.
So, the problem becomes:
15/20
After you divide, it is 0.75
The correct answer is 0.75