Refer to the table below Given that 2 of the 242 subjects ar

Refer to the table below. Given that 2 of the 242 subjects are randomly selected, complete parts (a) and (b).

                                           Group

          O         A          B          AB

Type Rh+       82          81         19        22

          Rh-        17          15          4         2

A. Assume that the selections are made with replacement. What is the probability that the 2 selected subjects are both group AB and type Rh+? (round to four decimal places as needed)

B. Assume the selections are made without replacement. What is the probability that the 2 selected subjects are both group AB and type Rh+? (round to four decimal places as needed)

Solution

Total number of person with the AB and Rh+ is 22   and the total sample population is 242

P(AB and Rh+) =22/242

A)With replacement =>

When selected subject choosen is firse AB and Rh+ =>P(AB and Rh+)=22/242

With replacement the probability =(22/242)^2 =.09^2 =.00826

B)Without replacement ,the probability is 22/242*21/241 =(22*21)/(242*241)=.0079