please help me, thank you!!!

We need to find the probability that a selected animal will be an threatened given they are a bird: P(T/B). So,
[tex] P(T/B)= \frac{P(T\cap B)}{P(B)} [/tex]
Where, Probability of threatened animal that are birds:
[tex] P(T \cap B) [/tex] = [tex] \frac{15}{475} [/tex]
and probability of bird=[tex] \frac{90}{475} [/tex]
Therefore, P(T/B)= \frac{P(T\cap B)}{P(B)}
= [tex] \frac{\frac{15}{475}}{\frac{90}{475}} [/tex]
=[tex] \frac{15}{90} [/tex]
=0.1667
=16.67%