Advertisements
Advertisements
प्रश्न
The circumference of a circle is equal to the perimeter of a square. The area of the square is 484 sq.m. Find the area of the circle.
Advertisements
उत्तर
Let the side of the square = s and the radius of the circle = r
∴ 2πr = 4s
But, the area of the square 484m2
∴ the side of the square
= `sqrt(484)`
= 22m
⇒ 2πr
= 4 x 22 ∈ r
= 14m
The Area of a Circle with radius r = πr2
The Area of a Circle with radius 14
= π(14)2
= `(22)/(7) xx (14)^2`
= 616m2.
APPEARS IN
संबंधित प्रश्न
The circumference of a circle exceeds diameter by 16.8 cm. Find the circumference of
circle.
The outer circumference of a circular race track is 528m. The track is everywhere 14m
wide. Calculate the cost of leveling the track at rate of 50 paise per square metre.
Choose the correct alternative answer for the following question.
A cone was melted and cast into a cylinder of the same radius as that of the base of the cone. If the height of the cylinder is 5 cm, find the height of the cone.
A race track is in the form of a rig whose inner circumference is 352 m and outer circumference is 396 m. Find the width and the area of the track.
Find the area grazed by a horse tied with a 11. 2 m rope to a corner of a field measuring 25m by 15 m.
A cart wheel makes 9 revolutions per second. If the diameter of the wheel is 42 cm, find its speed in km/hr.
Find the volume and the surface area of the spheres in the following :
Radius= 2.1 cm
In the adjoining figure, the crescent is formed by two circles which touch at the point A. O is the centre of bigger circle. If CB = 9 cm and DE = 5 cm, find the area of the shaded portion.

A 4.2m wide road surrounds a circular plot whose circumference is 176m. Find the cost of paving the road at Rs.75per m2.
Sudhanshu divides a circular disc of radius 7 cm in two equal parts. What is the perimeter of each semicircular shape disc? (Use π = `22/7`)
