Of 100 people, 50 are Democrats, 40 are Republicans, and 10 are Independents. The percentages of the

Question:

Of 100 people, 50 are Democrats, 40 are Republicans, and 10 are Independents. The percentages of the people in these three categories who read The Wall Street Journal are known to be 30, 60, and 40 percent, respectively. If one of these people is observed reading the Journal, what is the probability that he or she is a Republican?