Three companies, X, Y and Z supply computers to a university. The percentage of computers supplied by them and the probability of those being defective are tabulated below.
Company |
% of computers supplied |
Probability of being defective |
X |
60% |
0.01 |
Y |
30% |
0.02 |
Z |
10% |
0.03 |
Given that a computer is defective, the probability that it was supplied by Y is: [2 marks]
(A) 0.1
(B) 0.2
(C) 0.3
(D) 0.4
I got the correct answer by applying bayees theorem. But that theorem is applicable where the events are collectively exhaustive and mutual exclusive. These are collectively exhaustive but i don't think that they are mutually exclusive as Supplying of x does not mean that y wont supply.Please clear this doubt.