Answer:
Option D - 30 years
Explanation:
Given : Michelle is three times as old as Fiona. Fiona is twice as old as Madeline. Madeline is five years old.
To find : How old is Michelle?
Solution :
Let the Michelle is x years old.
The Fiona is y years old.
The Madeline is z years old.
According to question,
Madeline is five years old.
i.e. z=5
Fiona is twice as old as Madeline.
i.e.



Fiona is 10 years old.
Michelle is three times as old as Fiona.
i.e.



Michelle is 30 years old.
Therefore, Option D - 30 years old is correct.