Hello, I'm studying statistics on my own from "Probability and Statistics for Engineers and Scientists (Ronald E. Walpole, Raymond H. Myers Third Edition)", I happened to come across this exercise where my answer does not match the one in the book. Thank you for the help in advance.
Police plan to enforce speed limits by using radar traps at 4 diffferent locations within the city limits. The radar traps at each of the locations L1, L2, L3 and L4 are operated 40%, 30%, 20% and 30% of the time, and if a person who is speeding on his way to work has probabilities of 0.2, 0.1, 0.5 and 0.2 respectively, of passing through these locations, what is the probability that he will receive a speeding ticket ? The books stated answer is : 0.27 Mine is : 0.2450 [ reasoning as follows : 1- P(no ticket at L1) - P(no ticket at L2) - P(no ticket at L3) - P(no ticket at L4) ] Thanks again for the help G . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
