Chris commutes to work on two different routes A and B. If Chris comes home by route A, then he will be home before 6 P.M. with probability 0.9. If Chris chooses route B, then he will be home before 6 P.M. with probability 0.7. In the past, the proportion of times that Chris chose route A is 0.6. (a) What proportion of times is Chris home from his office before 6 P.M.? (b) If Chris is home after 6 P.M. today, what Solution a)P = (0.6*0.9)+(0.4*0.7) = 0.54+0.28 = 0.82 b)P = 0.4*0.3 = 0.12.