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AHHHHHHHHHHHHHHH SOMEONE ANSWEER THIS PLEEASEEE NEED ANSWER ASP 20 pts!! Please answer!!! I literally don't get this ;c so PLEASE help

Let P(A)=4/7 and P(B|A)=3/8 .


What is the probability of events A and B occurring?


Enter your answer as a fraction in simplest form.

1 Answer

5 votes

Answer:


P(A\textrm{ and }B)=(3)/(14)

Explanation:

Given:


P(A)=(4)/(7)


P(B|A)=(3)/(8)

We know that, conditional probability of B given that A has occurred is given as:


P(B|A)=(P(A\cap B)/(P(A)). Expressing this in terms of
P(A\cap B), we get


P(A\cap B)=P(B|A)* P(A)

Plug in the known values and solve for
P(A\cap B). This gives,


P(A\cap B)=P(B|A)* P(A)\\P(A\cap B)=(3)/(8)* (4)/(7)\\P(A\cap B)=(12)/(56)=(3)/(14)

Therefore, the probability of events A and B occurring is
(3)/(14).

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