Suppose that 6% of the people with blood group O are left handed and 10% of those with other blood groups are left handed 30% of the people have blood group O. If a left-handed person is selected at random, what is the probability that he/she will have blood group O?


Given condition can be represented as below:



Let E1 = event that the person selected is of group O


E2= event that the person selected is of other than blood group O


And E3= event that selected person is left handed


∴P(E1) =0.30, P(E2) =0.70


P(E3|E1) = 0.60 And P(E3|E2) =0.10


Using baye’s theorem, we have:








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