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

    Question

    Three solid Metallic cubes of edges 15cm, 17cm and 18cm

    are melted together to make a new cube. 296 cm3 of the melted material is lost due to improper handling. The area (in cm2) of the whole surface of the newly formed cube is:
    A 4378 Correct Answer Incorrect Answer
    B 4056 Correct Answer Incorrect Answer
    C 2904 Correct Answer Incorrect Answer
    D 3456 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Volume of all three cubes = 153 + 173 + 183 = 3375 + 4913 + 5832 = 14120 cm3 Now, 296 cm3 of the melted material is lost due to improper handling. Volume of new cube = 14120 – 296 = 13824 cm3 Side of new cube = 24 cm Total Surface area of new cube = 6 (side)² = 6 (24)² = 3456 cm ²

    Practice Next

    Relevant for Exams: