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सी.आई.एस.सी.ई.आयसीएसई ICSE Class 8

The Total Surface Area of a Cylinder is 6512 Cm2 and the Circumference of Its Bases is 88 Cm. Find: (I) Its Radius (Ii) Its Volume - Mathematics

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प्रश्न

The total surface area of a cylinder is 6512 cm2 and the circumference of its bases is 88 cm. Find:
(i) its radius
(ii) its volume

बेरीज
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उत्तर

Let r be the radius and h be the height of the given cylinder.
Circumference = 2πr = 88 cm (Given)

⇒ `2 xx 22/7 xx r = 88`cm

⇒ `r = 88 xx 7/22 xx 1/2`

⇒ r = 14 cm

Total surface area = `2pir(h + r) = 6512` cm2 (Given)

⇒ `88(h + 14) = 6512` (∵ `2pir = 88` cm and r = 14 cm)

⇒ `h + 14 = 6512/88`

⇒ h + 14 = 74 ⇒ h = 60 cm

∴ Volume of the cylinder = `pir^2h`

= `22/7 xx (14)^2 xx 60` cm3 = 36960 cm3

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पाठ 21: Surface Area, Volume and Capacity - Exercise 21 (D) [पृष्ठ २४३]

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सेलिना Concise Mathematics [English] Class 8 ICSE
पाठ 21 Surface Area, Volume and Capacity
Exercise 21 (D) | Q 7 | पृष्ठ २४३

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