New RBI Grade B 2025 Notification will come Soon! Enroll Here

    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]
    A 342 cm² Correct Answer Incorrect Answer
    B 242 cm² Correct Answer Incorrect Answer
    C 352 cm² Correct Answer Incorrect Answer
    D 395 cm² Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    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

    Practice Next

    Relevant for Exams: