Question
A solid hemisphere of diameter 8 cm is placed over a
cube whose side is 7 cm. Calculate the total surface area of the combined structure. [Use π = 3]Solution
ATQ,
Let the radius of the hemisphere be ‘r’ cm and the side of the cube be ‘s’ cm. Total surface area of the structure formed = = 5s² + (s² – πr²) + 2πr² = 5 × 7² + (7² – 3 × 4²) + 2 × 3 × 4² = 245 + (49 – 48) + 96 = 245 + 1 + 96 = 342 cm²
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