Answer
No it is not possible.
Work Step by Step
Order is important when writing a ratio. The quantity mentioned first is the numerator. The quantity mentioned second is the denominator.
When Amelia says that the ratio of her age and her mother's age is 5 to 3 that would mean that Amelia is 5 times older than her mother's age 3 times:
(Amelia age x 5)/ (mother's age x 3).
In any case this is not possible, since Amelia's mother is older than Amelia.
If Amelia would correct her statement to the ratio of 3 to 5, than she could be right. Example: Let's assume Amelia is 27:
$\frac{3 \cdot 9}{5 \cdot 9} = \frac{27}{45}$,
and Amelia's mother is 45 years old.
