SOLUTION: Suppose E,F are events in a sample space S. Suppose Pr (E|F)=3/4 and Pr (F|E)= 1/2 and Pr (EUF)=2/3. Find Pr (E) and Pr (F)

Algebra.Com
Question 1024793: Suppose E,F are events in a sample space S. Suppose Pr (E|F)=3/4 and Pr (F|E)= 1/2 and Pr (EUF)=2/3. Find Pr (E) and Pr (F)
Answer by robertb(5830)   (Show Source): You can put this solution on YOUR website!
P(E|F) = P(E∩F)/P(F) ==>P(F) = (4/3)P(E ∩ F)
P(F|E) = P(E∩F)/P(E) ==>P(E) = 2P(E ∩ F)
==> P(E U F) = P(E) + P(F) - P(E ∩F) = 2P(E ∩ F) + (4/3)P(E ∩ F) - P(E ∩F) = (7/3)P(E ∩F)
==> 2/3 = (7/3)P(E ∩F)
==> 2 = 7P(E ∩F), or
P(E ∩F) = 2/7.
==> P(E) = 2P(E ∩ F) = 4/7, and
==> P(F) = (4/3)P(E ∩ F) = 8/21.

RELATED QUESTIONS

Please please please help Suppose E,F are events in a sample space S. Suppose Pr... (answered by Edwin McCravy)
Suppose E and F are events in a sample space. Given that Pr(E)=2/3 and Pr(F)=1/3, if Pr... (answered by stanbon)
let S be a sample space and E and F be events associated with S. Suppose that P(E)=1/3,... (answered by ikleyn)
Please assist me with my homework: Suppose E and F are two INDEPENDENT events. Pr(E) = (answered by stanbon)
Please show me how to do these hard homework problems: 1. if Pr(E)= 0.59 then Pr(E')=? (answered by kingme18)
I need a tutor to show me if I did these problems the correct way. 1. Given Pr(E) =... (answered by robertb)
Suppose A and B are independent events in a sample space S. Given that Pr(A)=1/4... (answered by robertb)
Hello! If I could get help with the following question: Let E and F be events such... (answered by greenestamps)
F and G are independent events in sample space S. If Pr(F)=0.45 and Pr(G)=0.6, find the... (answered by AnlytcPhil)