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CEMC Gauss (Grade 7), 2009

Algebra Difficulty 2.0 Junior Find the answer Canada

Lara ate $\frac{1}{4}$ of a pie and Ryan ate $\frac{3}{10}$ of the same pie. The next day Cassie ate $\frac{2}{3}$ of the pie that was left. What fraction of the original pie was not eaten?

(A) $\frac{9}{10}$ (B) $\frac{3}{10}$ (C) $\frac{7}{60}$ (D) $\frac{3}{20}$ (E) $\frac{1}{20}$

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