Question
A right circular cylinder has the same radius as a
circle whose circumference is 220 units. The height of the cylinder is 20% less than its radius. Find the curved surface area of this cylinder.Solution
ATQ, Let radius of the circle (and cylinder) be = r. So, 2 * (22/7) * r = 220 Or, r = 220 * 7 / 44 r = 35 units Height of cylinder is 20% less than radius: Height = 35 * (100 − 20) / 100 = 35 * 80 / 100 = 28 units So, curved surface area of cylinder = 2 * (22/7) * 35 * 28 = 6160 unit²
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