Final answer:
Events A and B are independent if the knowledge that one occurred does not affect the chance the other occurs. In this case, we need to calculate the probabilities of being a junior and using earbuds, as well as the probability of being a junior and using earbuds at the same time.
Step-by-step explanation:
In this case, event A is being a junior and event B is using earbuds. To determine if events A and B are independent, we need to determine if P(A and B) is equal to P(A) * P(B).
Here is the calculation:
P(A) = probability of being a junior = [number of juniors] / [total number of students]
P(B) = probability of using earbuds = [number of students using earbuds] / [total number of students]
P(A and B) = probability of being a junior and using earbuds = [number of juniors using earbuds] / [total number of students]
If P(A and B) is equal to P(A) * P(B), then events A and B are independent.