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CEMC Gauss (Grade 8), 2008

Number theory Difficulty 1.0 Junior Find the answer Canada

The numbers $3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13$ are written on separate cards and placed face down on a table. A card is chosen at random and flipped over. What is the probability that the number on this card is a prime number?

(A) $\frac{2}{11}$ (B) $\frac{4}{11}$ (C) $\frac{6}{11}$ (D) $\frac{3}{11}$ (E) $\frac{5}{11}$

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