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  1. Chapter 11 Class 7 Perimeter and Area
  2. Serial order wise

Transcript

Ex 11.3, 9 Shazli took a wire of length 44 cm and bent it into the shape of a circle. Find the radius of that circle. Also find its area. If the same wire is bent into the shape of a square, what will be the length of each of its sides? Which figure encloses more area, the circle or the square? (๐‘‡๐‘Ž๐‘˜๐‘’ ๐œ‹=22/7) Radius = r = ? Wire is bent into the shape of circle โˆด Length of wire = Circumference of circle 44 = 2๐œ‹r 44 = 2 ร— 22/7 ร— r (44 ร— 7)/44 = r 7 = r r = 7 cm โˆด Radius of given circle is 7 cm Area of circle Area of given circle = ๐œ‹r2 = 22/7 ร— (7)2 = 22/7 ร— 7 ร— 7 = 154 cm2 โˆด Area of circle is 154 cm2 Wire is bent to form a square Side of square = a = ? As wire is bent into the shape of square Length of wire = Perimeter of square 44 = 4a 44/4 = a 11 = a a = 11 cm Area of square Area of square = a ร— a = 11 ร— 11 = 121 cm2 โˆด Area of square is 121 cm2 Now, Area of circle is 154 cm2 Area of square is 121 cm2 So, circle encloses more area than square

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.