A bag of marbles contains 16 blue, 8 green, 9 red, 12 yellow and 5 black marbles. What is the probability of drawing a red marble?
Write your answer as a decimal.
The total number of marbles in the bag is 16 + 8 + 9 + 12 + 5 = <<16+8+9+12+5=50>>50.
The probability of drawing a red marble is 9/50.
As a decimal, the probability is 0.18. Answer: \boxed{0.18}.