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CEMC Gauss (Grade 8), 2009

Combinatorics Difficulty 2.0 Junior Find the answer Canada

A jar contains quarters (worth $0.25 each), nickels (worth $0.05 each) and pennies (worth $0.01 each). The value of the quarters is $10.00. The value of the nickels is $10.00. The value of the pennies is $10.00. If Judith randomly chooses one coin from the jar, what is the probability that it is a quarter?

(A) $\frac{25}{31}$ (B) $\frac{1}{31}$ (C) $\frac{1}{3}$ (D) $\frac{5}{248}$ (E) $\frac{1}{30}$

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