A bag contains 12 marbles: 5 red, 4 blue, 2 black and 1 whit…

A bag contains 12 marbles: 5 red, 4 blue, 2 black and 1 white. A marble is taken out of the bag, its colour recorded and then returned to the bag. After 20 trials, a blue marble had been selected 9 times. The fraction, 9 20 represents the _______ probability of picking a blue marble.