SOLUTION
Given:
[tex]P(\text{gas)}=0.89[/tex][tex]P(\text{Gas \& Oil) = 0.05}[/tex][tex]P(\text{Oil) = 0.07}[/tex](a)What is the probability that a driver purchases gasoline, given that he or she purchases oil:
[tex]=\frac{P(\text{Gas \& Oil)}}{P(Oil)}[/tex][tex]=\frac{0.05}{0.07}[/tex][tex]\begin{gathered} =0.71429 \\ =0.71\text{ (to the nearest hundredth)} \end{gathered}[/tex]The answer is 0.71
b) What is the probability that a driver purchases oil, given that he or she purchases gasoline:
[tex]\begin{gathered} =\frac{P(\text{Gas \& Oil)}}{P(Gas)} \\ =\frac{0.05}{0.89} \\ =0.05617 \\ =0.06\text{ (to the nearest hundredth)} \end{gathered}[/tex]The answer is 0.06