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Problem 3

Combinatorics Difficulty 1.0 Find the answer CEMC Pascal · Canada · 2005

Six balls, numbered $2, 3, 4, 5, 6, 7$ , are placed in a hat. Each ball is equally likely to be chosen. If one ball is chosen, what is the probability that the number on the selected ball is a prime number?

(A) $\dfrac{1}{6}$ (B) $\dfrac{1}{3}$ (C) $\dfrac{1}{2}$ (D) $\dfrac{2}{3}$ (E) $\dfrac{5}{6}$

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