maria is one-ninth as old as her mother. in 3 years, she will be one-fifth as old as her mother will be then. find their presant age.
Let the mother's age be $\displaystyle M$
Then Maria's current age is $\displaystyle \frac M9$
in three years time, maria will be $\displaystyle \frac M9 + 3$ years old, and her mother will be $\displaystyle M + 3$ years old. Since at this time, Maria's age will be one-fifth of her mother's age, we have:
$\displaystyle \frac M9 + 3 = \frac 15 (M + 3)$
Now solve for $\displaystyle M$ and you can find their ages