CEMC Cayley, 2005

Geometry Difficulty 3.0 AMC 10/12 Find the answer Canada

The base of a triangular piece of paper $ABC$ is 12 cm long. The paper is folded down over the base, with the crease $DE$ parallel to the base of the paper. The area of the triangle that projects below the base is 16% that of the area of the triangle $ABC$ . The length of $DE$ , in cm, is

(A) $9.6$ (B) $8.4$ (C) $7.2$ (D) $4.8$ (E) $6.96$

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