Ex 11.3, 9 - Chapter 11 Class 7 Perimeter and Area
Last updated at Dec. 12, 2018 by Teachoo
Ex 11.3
Ex 11.3, 1 (a)
Ex 11.3, 1 (b) Important
Ex 11.3, 1 (c)
Ex 11.3, 2 (a) Important
Ex 11.3, 2 (b) Important
Ex 11.3, 2 (c)
Ex 11.3, 3
Ex 11.3, 4 Important
Ex 11.3, 5 Important
Ex 11.3, 6
Ex 11.3, 7 Important
Ex 11.3, 8
Ex 11.3, 9 Important You are here
Ex 11.3, 10 Important
Ex 11.3, 11
Ex 11.3, 12 Important
Ex 11.3, 13 Important
Ex 11.3, 14
Ex 11.3, 15
Ex 11.3, 16 Important
Ex 11.3, 17 Important
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? (𝑇𝑎𝑘𝑒 𝜋=22/7) Radius = r = ? Wire is bent into the shape of circle ∴ Length of wire = Circumference of circle 44 = 2𝜋r 44 = 2 × 22/7 × r (44 × 7)/44 = r 7 = r r = 7 cm ∴ Radius of given circle is 7 cm Area of circle Area of given circle = 𝜋r2 = 22/7 × (7)2 = 22/7 × 7 × 7 = 154 cm2 ∴ 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 × a = 11 × 11 = 121 cm2 ∴ 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
