text: discrete probability (again)? discrete probability? 1)phenotype frequencies for east indians living in trinidad and tobago are as follows:  type o(38.2%) a(20.6%)      b(34.2%) ab(6.9%)  two people from this population are selected at random, find the following probabilities and comment: a) the two people have the same blood group b) the two people have the same blood group a. c) there is a crime stain that is blood group a. find the probability that exactly one of the two has the same blood group as the stain. a) p(the same group) = 0.382*0.382 + 0.206*0.206+0.342*0.342+0.069*0.069  b)p(the two are of group a)=0.206*0.206  c)p(exactly one is a) = 2*(0.206*(1-0.206))                        =2*0.206*0.794