Ex 6.1, 7 (ii)

Transcript

Ex 6.1, 7 (ii) Find the total perimeter of all the petals in each of the given flowers. Let’s look at 1 arc We observe that in 1 arc, we get form an equilateral triangle of side 42 cm Since it is an equilateral triangle, all angles are 60° Thus, we have radius = 42 cm and 𝜃 = 60° for 1 arc And, we have 6 × 2 = 12 arcs in total Thus, Perimeter of shape = 12 × Length of arc with radius 42 cm & Angle 60° = 12 × 2𝜋𝑟 × 𝜃/(360° ) = 12 × 2𝜋𝑟 × 𝜃/(360° ) = 12 × 𝟐 ×𝟐𝟐/𝟕 × 𝟒𝟐 × (𝟔𝟎° )/(𝟑𝟔𝟎° ) = 12 × 2 ×22/7 × 42 × 1/6 = 12 × 2 ×22/7 × 7 = 12 × 2 × 22 = 528 cm