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सी.आई.एस.सी.ई.आयसीएसई ICSE Class 7

The Circumference of a Circle Exceeds Its Diameter by 18 Cm. Find the Radius of the Circle. - Mathematics

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प्रश्न

The circumference of a circle exceeds its diameter by 18 cm. find the radius of the circle.

बेरीज
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उत्तर

Let c be the circumference and d be the diameter of the circle.

∴ c = d + 18

⇒ dπ = d + 18 ⇒ dπ − d = 18

d(π − 1) = 18

⇒ `"d"(22/7-1)` = 18

⇒ `"d"(15/7) =18`

⇒ d =`(18xx7)/15=126/15` = 8.4 cm

∴ Radius =`"d"/2=8.4/2` = 4.2 cm

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पाठ 20: Mensuration - Exercise 20 (B)

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सेलिना Concise Mathematics [English] Class 7 ICSE
पाठ 20 Mensuration
Exercise 20 (B) | Q 28

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