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प्रश्न
Find the height of the cylinder whose radius is 7 cm and the total surface area is 1100 cm2.
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उत्तर
Total surface area =1100 cm2
Radius = 7 cm
Let height of the cylinder = h
Then, total surface area = 2πr(h + r)
⇒ `2 xx 22/7 xx 7(h + 7) = 1100`
⇒ `44(h + 7) = 1100`
⇒ `44h + 308 = 1100`
⇒ `44h = 1100 - 308`
h = `792/44 = 18` cm
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