P(A and B) with probability tree
You are currently viewing a sample of the Cram Kit. Click here to unlock everything.
Scenario: Given the following probability tree, find the probability that a student did not wear a hat and received a bid from Delta Apple Pi.
P(A ∩ B) = P(A | B) x P(B)
Event A = received a bid
Event B = did not wear a hat
P(A ∩ B) = 0.20 x 0.60
P(A ∩ B) = 0.12
Answer: The probability that a recruit did not wear a hat and received a bid from Delta Apple Pi is 0.12.
On entire tree...
0.30 + 0.10 + 0.12 + 0.48 = 1.00 (a.k.a. 100%)
Solving for P(B)
Scenario: Given the following probability tree, find the probability that a student received a bid from Delta Apple Pi.
P(B) = 0.30 + 0.12
P(B) = 0.42
Answer: The probability that a student received a bid from Delta Apple Pi is 0.42.