Two students, Jim and Joan, are registered for the same class and attend independently to each other, Jim 91.9% of the time and Joan 84.3% of the time. What is the probability that on any given day
a) at least one of them will be in class?
b) neither will be in class?
prob(Jim AND Joan) = .919(.843) = .774717
a) Prob(Jim OR Joan) = Prob(Jim) + prob(Joan) - P(Jim AND Joan)
= .919 + .843 - .774717 = .987
b) prob(neither is in class) = (.081)(.157) = .0127