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2015 AMC 10B Question 11

AMC10 · 2015 AMC 10B

Question 11

Among the positive integers less than $100,$ each of whose digits is a prime number, one is selected at random. What is the probability that the selected number is prime?
  1. $ \dfrac{8}{99} $
  2. $ \dfrac{2}{5} $
  3. $ \dfrac{9}{20} $
  4. $ \dfrac{1}{2} $
  5. $ \dfrac{9}{16} $