Question

A square piece of paper is folded three times along its diagonal to get an isosceles triangle whose equal sides are 10 cm. What is the area of the unfolded original piece of paper?

Accepted Answer

A. The folded paper forms an isosceles right triangle with legs = 10 cm. Area of this final triangle = $\frac{1}{2} 	imes 10 	imes 10 = 50 	ext{ sq. cm.}$ Each fold halves the area. Unfolding 3 times multiplies the area by $2^3 = 8$. Area of original square = $50 	imes 8 = 400 	ext{ sq. cm.}$

Geometry: Folded Paper Area

Explanation

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