461,386 views
27 votes
27 votes
the probability that a randomly-selected IRSC student is an athlete is 0.16 the probability that a randomly-selected RSE student is a biology major is 0.12 the probability that a randomly-selected RS student is biology major in and out 30 is 0.11 calculate the following probability round the solution to the 3rd decimal place if necessary

User Vdvaxel
by
3.0k points

1 Answer

19 votes
19 votes

The formula for the conditional probability is as follows:


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

where P(A|B) is the probability of A given B, P(A∩B) is the probability of A and B, and P(B) is the probability of B. Note that P(A∩B)=P(B∩A).

In the given problem, we have the following:


\begin{gathered} P(A)=0.16 \\ P(B)=0.12 \\ P(A\cap B)=P(B\cap A)=0.11 \end{gathered}

where A stands for athlete and B stands for biology major.

Thus, for P( biology major | athlete), we have the following:


\begin{gathered} P(B|A)=(P(B\cap A))/(P(A)) \\ =(0.11)/(0.16) \\ =0.6875 \\ \approx0.688 \end{gathered}

For P(athlete | biology major), we have the following:


\begin{gathered} P(A|B)=(P(A\cap B))/(P(B)) \\ =(0.11)/(0.12) \\ =0.916\bar{6} \\ \approx0.917 \end{gathered}

User Human
by
2.2k points