Question

    A closed wooden box of uniform thickness has length,

    breadth and height 20cms, 16cms and 12 cms respectively. If the thickness of the wooden block is 2 cms. What would be the inner surface area of the box?
    A 830 cm² Correct Answer Incorrect Answer
    B 845 cm² Correct Answer Incorrect Answer
    C 832 cm² Correct Answer Incorrect Answer
    D 840 cm² Correct Answer Incorrect Answer

    Solution

    Inner length = 16 cm Inner width = 12 cm Inner height = 8 cm Inner surface area = 2(lb + bh + lh) = 2 (16 × 12 + 12 × 8 + 8 × 16 ) = 2 (192 + 96 + 128) = 2 × 416 = 832 cm2.

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