CEMC Fermat, 2008

Algebra Difficulty 2.0 Junior Find the answer Canada

On seven tests, each out of $100$ marks, Siobhan received marks of $69, 53, 69, 71, 78, x,$ and $y$ . If her average mark on the seven tests is $66$ , then the minimum possible value of $x$ is

(A) $22$ (B) $68$ (C) $61$ (D) $53$ (E) $0$

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