Alec attended his town's annual Worm Charming Competition. Contestants are assigned to a square foot of land, where they have 30 minutes to "charm" worms to the surface of the dirt using a single technique. Alec observed contestants' charming techniques, and kept track of how many worms surfaced. Tapping the ground Raking the ground 5-10 worms 6 11-20 worms 5 10 5 8 4 21-30 worms What is the probability that a randomly selected contestant charmed 11-20 worms or 5-10 worms? Simplify any fractions.