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2015 AMC 10B Problem 11

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2015 AMC 10B Problem 11AMC 10 Step by Step
Name:                             Date: September 13, 2026
Primes · difficulty 2 of 5 · about 3 min · position P11-15

Among the positive integers less than 100100 , each of whose digits is a prime number, one is selected at random. What is the probability that the selected number is prime?

  1. A)

    899\dfrac{8}{99}

  2. B)

    25\dfrac{2}{5}

  3. C)

    920\dfrac{9}{20}

  4. D)

    12\dfrac{1}{2}

  5. E)

    916\dfrac{9}{16}

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