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The length, breadth and height of a rectangular solid are in ratio 5:4:2. If its total surface area is1216 cm2, find the volume of the solid. |
Answer» Given,that the ratio in length, breadth and height of a RECTANGULAR solid = 5 : 4 : 2 Total surface area =1216 cm² Let’s assume the length = 5x, breadth = 4x and height = 2X Total surface area = 2[5x × 4x + 4x × 2x + 2x × 5x] = 2[20x2 + 8x2 + 10x2 ] = 2 × 38x² = 76x² So, 76x² = 1216 ⇒ x² = 1216/76 = 16 = (4)² ∴ x = 4 Hence,the dimensions of the rectangular solid are Length = 5 × 4 = 20 cm Breadth = 4 × 4 = 16 cm Height = 2 × 4 = 8 cm and volume = lbh = 20 × 16 × 8 = 2560 cm³ |
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