Question

    Suppose the ratio of the radius to the height of a

    cylinder is 2:3, then what is the volume of the cylinder when the total surface area of the cylinder is 770 square centimeters?
    A 1520 Correct Answer Incorrect Answer
    B 1665 Correct Answer Incorrect Answer
    C 1617 Correct Answer Incorrect Answer
    D 2150 Correct Answer Incorrect Answer
    E none of these Correct Answer Incorrect Answer

    Solution

    ATQ, Let the radius of the cylinder = '2r' cm Height of the cylinder = '3r' cm Total surface area of cylinder = 770 cm2 {2 × (22/7) × 2r × 3r + 2 × (22/7) × 2r × 2r} = 770 (44/7) (6r2 + 4r2) = 770 10r2 = 122.5 r2 = 12.25 r = 3.5 Radius of the cylinder = 7 cm Height of the cylinder = 10.5 cm Volume of the cylinder = (22/7) × 7 × 7 × 10.5 = 1617 cm3

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