AP BIOLOGY

Detailed explanation-1: -P(Ac) = 100%-P(A). The complement rule can be derived from the axioms: the union of A and its complement is S (either A happens or it does not, and there is no other possibility), so P(AUAc) = P(S) = 100%, by axiom 2.

Detailed explanation-2: -P(A) = n(A)/n(S) P(A) is the probability of an event “A” n(A) is the number of favourable outcomes. n(S) is the total number of events in the sample space.

Detailed explanation-3: -If two events, A and B are mutually exclusive then, P(A U B) = P(A) + P(B). This follows immediately from (3). Since A and B are mutually exclusive, n(A ∩ B)=0 and so P(A ∩ B)=0.

Detailed explanation-4: -Formula for the probability of A and B (independent events): p(A and B) = p(A) * p(B). If the probability of one event doesn’t affect the other, you have an independent event. All you do is multiply the probability of one by the probability of another.