Question:
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?
Solution:
Let’s assume
E1 = The event that a person selected is of blood group O
E2 = The event that the people selected is of other group
And H = The event that selected person is left handed
Now,
P(E1) = 0.30 and P(E2) = 0.70
Further, P(H/E1) = 0.06 and P(H/E2) = 0.10
Using Baye’s Theorem, we have
Therefore, the required probability is 9/44.