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प्रश्न
Curved surface area of a cylinder is 1980 cm2 and radius of its base is 15 cm. Find the height of the cylinder. (π = `22/7`)
उत्तर
Let the height of the cylinder be h cm.
Radius of the cylinder, r = 15 cm
Curved surface area of the cylinder = 1980 cm2
∴ 2πrh = 1980 cm2
⇒ `2 xx 22/7 xx 15 xx "h" = 1980`
⇒ `"h" = [ 1980 xx 7]/(2 × 22 × 15)`
⇒ `"h" = [cancel(1980)^3 xx 7]/cancel(660)_1`
⇒ h = 3 × 7
⇒ h = 21 cm
Thus, the height of the cylinder is 21 cm.
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