Suppose that exam scores were distributed normally. Let the mean be 80 and standard deviation be 8. If it is known that a student's score is greater than 75, what is the probability that his score is greater than 90?
I am a bit confused by the wording of the question. Should this be considered a case of conditional probability? Is my approach correct?
This is know I thought about it:
$$P(Y > 90 | Y >75) = \frac{P(Y > 90 \cap Y > 75)}{P(Y > 75)} = \frac{P(Y > 90)}{P(Y > 75)}.$$