Advertisements
Advertisements
प्रश्न
The radius of a circle is 21 cm. Find the circumference (Take π = `3 1/7`).
उत्तर
Given, radius (r) = 21 cm and π =`22/7`
Circumference of the circle = 2πr
= `2xx22/7xx21` cm
= 2 × 22 × 3 cm
= 132 cm
APPEARS IN
संबंधित प्रश्न
A car travels 1 km distance in which each wheel makes 450 complete revolutions. Find the radius of wheel.
A playground has the shape of rectangle, with two semicircles on its smaller sides as diameters, added to its outside. If the sides of rectangle are 36m and 24.5m. find the area of playground.
The sum of the radii of two circles is 7 cm, and the difference of their circumferences is 8 cm. Find the circumference of the circles.
The sum of the radii of two circles is 10.5 cm and the difference of their circumferences is 13. 2 cm. Find the radii of the two circles.
A lawn is in the shape of a semi-circle of diameter 42 m. The lawn is surrounded by a flower bed of width 7 m all around. Find the area of the flower bed in m2 .
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.
Find the circumference of a circle whose area is 81πcm2.
A wire in the form of a circle of radius 42cm. It is bent into a square. Determine the side of the square and compare the area of the regions enclosed in the two cases.
A wire of length 1320 cm is made into circular frames of radius 7 cm each. How many frames can be made?
Find the total cost of wooden fencing around a circular garden of diameter 28 m, if 1 m of fencing costs ₹ 300.
