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The area of a circle is 98.56 cm2. Find its circumference.
In order to solve such type of questions we basically need to find the radius of the give circle and simply use it to find the are circumference or perimeter of the given circle.
Given the area of the circle = 98.56 cm2
And we also know, Area of the circle = πr2
Therefore, πr2 = 98.56
(put value of π = 22/7)
On rearranging we get,
⟹ r = √31.36
⇒ r = 5.6 cm
So, the radius of the circle = 5.6 cm
And we know, Perimeter of circle = 2πr
(put value of r)
⇒ Circumference or Perimeter of circle = 2π(5.6)
= 35.2 cm
The circumference or perimeter of the circle is 35.2 cm
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.]