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प्रश्न
The radius and height of a cylinder are in the ratio of 5 : 7 and its volume is 550 cm. Find its radius. (Take π = 22/7)
उत्तर
Let the radius of the base and height of the cylinder be 5x cm and 7x cm respectively.
Then,
Volume = 550 cm3
⇒ `22/7 xx (5x)^2 xx 7x = 550`....( Use, r = 5x, h = 7x and volume = πr2h )
⇒ `22/7 xx 25x^2 xx 7x = 550`
⇒ 22 x 25x3 = 550
⇒ 550x3 = 550
⇒ x3 = 1
⇒ x = 1
Hence, radius of the cyclinder = 5x cm = ( 5 x 1 ) cm = 5 cm.
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