# Ex 11.3, 11 - Chapter 11 Class 7 Perimeter and Area

Last updated at Dec. 12, 2018 by

Last updated at Dec. 12, 2018 by

Transcript

Ex 11.3, 11 A circle of radius 2 cm is cut out from a square piece of an aluminum sheet of side 6 cm. What is the area of the left over aluminum sheet? (Take π = 3.14) Let ABCD be the square sheet of side 6 cm Remaining Area = Area of square sheet − Area of circular piece Area of square sheet Side of sheet = a = 6 cm Area of square sheet = a × a = 6 × 6 = 36 cm2 Area of circular Radius of circular = r = 2 cm Area of circular = 𝜋r2 = 3.14 × (2)2 = 314/100 × 4 = 1256/100 = 12.56 cm2 Now, Remaining Area = Area of square sheet − Area of circular piece = 36 − 12.56 = 36 − 1256/100 = (36 × 100 − 1256)/100 = (3600 − 1256)/100 = 2344/100 = 23.44 cm2 ∴ 23.44 cm2 of area is left.

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

Ex 11.3, 10 Important

Ex 11.3, 11 You are here

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

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.