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A Circular Field Cf Radius 105 M Has a Circular Path of Uniform Width of 5 M Along and Inside Its Boundary. Find the Area of the Path.

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Question

A circular field of radius 105 m has a circular path of uniform width of 5 m along and inside its boundary. Find the area of the path.

Sum
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Solution

The radius of circular field, `r_1 = 105`m

Width of path = 50 m

∴ The radius of the inner circle, `r_2 = 105 - 5 = 100`m

Area of path = `pir_1^2 - pir_2^2`

= `22/7[(105)^2 - (100)^2]`

= `22/7(105 + 100)(105 - 100)`

= `22/7 xx 205 xx 5`

= `22550/7`m2 

= `3221 3/7`m2

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Chapter 22: Area of a Trapezium and a Polygon - Exercise 20 (D) [Page 234]

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Selina Concise Mathematics [English] Class 8 ICSE
Chapter 22 Area of a Trapezium and a Polygon
Exercise 20 (D) | Q 8 | Page 234

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