हिंदी
सी.आई.एस.सी.ई.आईसीएसई ICSE Class 8

Find the area of the shaded portion in each of the following diagrams:

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प्रश्न

Find the area of the shaded portion in each of the following diagrams:

(i)

(ii)

योग
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उत्तर

(i)

Radius of circle, r = 7 cm

∴ Side of square = 7 + 7 = 14 cm

Area of circle = `pir^2`

= `22/7 xx 7xx 7`

= 154 cm2

Area of square = `14 xx 14`

= 196 cm2

∴ Area of shaded portion = 196 - 154

= 42 cm2

(ii)

Radii of concentric circles are

`r_1 = 4.5`m

`r_2 = 2.5`m

∴ Area of shaded portion = `pir_1^2 - pir_2^2`

= `pi[r_1^2 - r_2^2] = 22/7[(4.5)^2 - (2.5)^2]`

= `22/7 xx (4.5 + 2.5) (4.5 - 2.5)`

= `22/7 xx 14 = 44` cm2

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अध्याय 22: Area of a Trapezium and a Polygon - Exercise 20 (D) [पृष्ठ २३४]

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सेलिना Concise Mathematics [English] Class 8 ICSE
अध्याय 22 Area of a Trapezium and a Polygon
Exercise 20 (D) | Q 6 | पृष्ठ २३४

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