Answer:
Events departing on time and arriving on time are NOT independent.
Explanation:
If two events A and B are independent, then
P(A and B) = P(A) * P(B)
Here
A = flights depart on time
B = flights arrive on time
P(A) = 0.90
P(B) = 0.80
If A and B are independent, then
P(A and B) = P(A) * P(B) = 0.9 * 0.8 = 0.72
Since
the observed value of P(A and B) is 0.75,
assuming that there are no observation errors, we conclude that the two events A and B are not independent.
