The Circumference of a Circle Exceeds Its Diameter by 450 Cm. Find the Area of the Circle. - Mathematics

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Sum

The circumference of a circle exceeds its diameter by 450 cm. Find the area of the circle.

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Solution

Let the radius of a circle = r cm
⇒ Circumference of a circle = 2πr cm
Diameter of a circle = 2r cm
Now, Circumference of a circle - Diameter of a circle = 450m
⇒ 2πr - 2r = 450
⇒ 2r(π - 1) = 450

⇒ `2"r"(22/7 - 1)` = 450

⇒ `2"r" xx (15)/(7)` = 450

⇒ r = `(450 xx 7)/(2 xx 15)`
= 105cm

∴ Area of a circle
= πr2

= `(22)/(7) xx 105 xx 105`
= 34650cm2.

  Is there an error in this question or solution?
Chapter 24: Perimeter and Area - Exercise 24.3

APPEARS IN

Frank Class 9 Maths ICSE
Chapter 24 Perimeter and Area
Exercise 24.3 | Q 6

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