Youssef has baked 6 pancakes for Olivia, 3 of them plan and 3 stuffed with blueberries. Olivia wants to make sure that she tastes both kinds of pancakes, but they all look alike, so she starts eating pancakes at random until she has eaten at least one plain pancake and at least one stuffed with blueberries. When this happens, Olivia sops eating and leaves the remaining pancakes on the plate What is the probability that at the end exactly pancakes remain on the plate? CAO 9 OB 39 c 000 D 20