Answer:
18/25
Explanation:
We want to find the probability that a student has a dog given that they have a cat. Its important to note that we are only looking at the side that says " has a cat " as we are given that the student would have a cat. So the side that says "does not have a cat" is irrelevant for this question.
Again probability = # of favorable outcomes ( what we are looking for to happen, a student having a dog given they have a cat ) / total # of possible outcomes ( the total # of students that have a cat )
The # of students that have a dog and a cat = 18 so # of favorable outcomes = 18
The total # of students that have a cat regardless of having a dog or not = 18 + 7 = 25
So probability of choosing a student that has a dog given they have a cat = 18/25