Trevor and Marla are brother and sister. I ftrevor is 3/5 of Marla's age, and trevor is 15, how old is Marla?

Marla is 25.

To find out Marla's age, we can set up an equation using the given information.

Let's say Marla's age is x.

According to the given information, Trevor is 3/5 of Marla's age, so we can write the equation:

Trevor's age = (3/5) * Marla's age

We also know that Trevor is 15 years old, so we substitute that into the equation:

15 = (3/5) * Marla's age

To solve for Marla's age, we need to isolate Marla's age on one side of the equation. We can achieve this by multiplying both sides of the equation by 5/3 (the reciprocal of 3/5):

(15) * (5/3) = (3/5) * (Marla's age) * (5/3)

By simplifying the equation, we get:

25 = Marla's age

Therefore, Marla is 25 years old.