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प्रश्न
From a rectangular solid of metal 42 cm by 30 cm by 20 cm, a conical cavity of diameter 14 cm and depth 24 cm is drilled out. Find: the weight of the material drilled out if it weighs 7 gm per cm3.
उत्तर
Weight of material drilled out
=1232 × 7 g = 8624g = 8.624 kg
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