Is it conditional probability or not? What is the result?
You walk into a Las Vegas casino. There are 10 slot machines. 9 of them win 20% of the time. 1 of them, the lucky machine, wins 30% of the time. But you don't know which one is the lucky one (the 30% winner). You watch someone put a quarter into the machine and win. What is the chance it was the "lucky" machine?
Express your answer as a fraction or as a decimal with 2 significant digits