Answer:
24/45
Explanation:
If 15 is your original denominator, you can take 45/15 to get 3, multiply 8/15 by 3, and get your answer. Alternatively, if you have a question like this you can also do 8/15 and get 5.333-, once you have that you can just plug numbers into, ?/45 thus by trial and error getting the answer.