A candy jar contains several small pieces of candy: • 5 miniature peanut butter cups • 7 dark chocolate candy bars • 8 gummy worms Roger randomly selected one piece of candy from the jar. What is the probability in decimal form that the candy Roger selected was NOT a gummy worm?
There are a total of 5 + 7 + 8 = <<5+7+8=20>>20 pieces of candy in the jar.
There are 8 gummy worms, so the probability of selecting a gummy worm is 8/20 = <<8/20=0.4>>0.4.
The probability of not selecting a gummy worm is 1 - 0.4 = 0.6 (in decimal form). Answer: \boxed{0.6}.