The perimeter of the quadrant of a circle is 25 cm. Find its area.
We know perimeter of a sector = Length of its arc + 2R → eqn1
Where R = radius of the sector.
Perimeter = 25 cm
θ = 90°
⇒ R = 7 cm → eqn2
∴ Area of the quadrant = 38.5 cm2
Area of the quadrant is 38.5 cm 2.
ABCD is a field in the shape of a trapezium, AD || BC, ∠ABC = 90° and ∠ADC = 60°. Four sectors are formed with centres A, B, C and D, as shown in the figure. The radius of each sector is 14 m.
Find the following:
(i) total area of the four sectors,
(ii) area of the remaining portion, given that AD = 55 m, BC = 45 m and AB = 30 m.
A child draws the figure of an aeroplane as shown. Here, the wings ABCD and FGHI are parallelograms, the tail DEF is an isosceles triangle, the cockpit CKI is a semicircle and CDFI is a square. In the given figure, BP ⊥ CD, HQ ⊥ FI and EL ⊥ DF. If CD = 8 cm, BP = HQ = 4 cm and DE = EF = 5 cm, find the area of the whole figure. [Take π = 3.14.]