Answer:0.789
Step-by-step explanation:
20 % person smokes and 80 % don't smoke
Probability that a smoker gets lung cancer=15%
Probability that a non smoker gets lung cancer is =1%
Thus
Probability if a person is diagnosed with cancer he/she is a smoker
P=[tex]\frac{Smoker}{Given he gets cancer}[/tex]
P=[tex]\frac{0.2\times 0.15}{0.8\times 0.01+0.2\times 0.15}[/tex]
P=[tex]\frac{0.03}{0.038}[/tex]=0.789