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A square pyramid is made from a solid cube having edge 30cm. Calculate the surface area. |
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Answer» Base edge of the square pyramid = 30 cm Height = 30 cm Slant height = \(\sqrt{30^2+15^2}\) = \(\sqrt{900+225}\) = \(\sqrt{1125}\) = \(15\sqrt{5}\) Lateral surface area = \(4\times\frac{1}{2}\times15\sqrt{2}\times30\) = 60 x 15√5 = 900√5 sq.cm Total surface area = 900 + 900√5 = 900(1 + √5) sq.cm |
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