Given, P(E) = 0.3, P(E ∪ F) = 0.5
Also, E and F are independent, then
P (E ∩ F)=P(E).P(F)
We know, P(E ∪ F)=P(E)+P(F)- P(E ∩ F)
P(E ∪ F)=P(E)+P(F)- [P(E) P(F)]
0.5 = 0.3 + P(F)-0.3P(F)
0.5-0.3 = (1- 0.3) P(F)
P(F) = (0.5 -0.3)/0.7
P(F) = 2/7
Since P(E|F)-P(F|E)
P(E|F)-P(F|E) = 1/70