Question three

A support group for people wanting to quit smoking encourages both current smokers and previous smokers (who have successfully quit smoking) to participate in group sessions. In a particular group session, one volunteer among the current smokers was asked what age they started smoking (let this age be denoted by X) and one volunteer among the previous smokers was asked what age they quit smoking (let this age be denoted by Y). Suppose that the relationship between X and Y is described by the following joint probability distribution: y (Previous smoker) 54 72 80 15 0.11 0.15 0.13 :1: (Current smoker) 22 0.13 0.11 0.09 31 0.15 0.07 0.06 Calculate the expected value of X2 (Y 54). Do not include any units in your