Answer:
c. 0.7404
Step-by-step explanation:
We can use Bayes Formula,
[tex] P(N|C) = \frac{P(C|N)*P(N)}{P(C)} [/tex]
We know every single value of that expression except P(C). We can calculate C by dividing into 2 cases: if the customer is new or not.
By the total probability theorem, we know that P(C) = P(C|N)*P(N) + P(C|N')*P(N') = 0.5*0.8 + 0.7*0.2 = 0.4+0.14 = 0.54
We replace P(C) on the equation above and we obtain
[tex] P(N|C) = \frac{P(C|N)*P(N)}{P(C)} = \frac{0.5*0.8}{0.54} = 0.7407[/tex]
Thus, P(N|C) = 0.7407. Answer c is correct
I hope this helped you!