Advertisements
Advertisements
प्रश्न
Find the radius and area of a circle, whose circumference is :
(i) 132 cm
(ii) 22 m
Advertisements
उत्तर
(i)
Circumference of circle = 132 cm
2πr = 132
`2 xx 22/7 xx r = 132`
`r = (132 xx 7)/(2 xx 22)`
`r = 21`cm
∴ Area of circle = `pir^2`
= `22/7 xx 21 xx 21`
= 1386 cm2
(ii)
circumference of circle = 22 m
∴ `2pir = 22`
`2 xx 22/7 xx r = 22`
`r = (22 xx 7)/(2 xx 22)`
r = `7/2`
r = 3.5 m
Area of circle = `pir^2`
= `22/7 xx 3.5 xx 3.5`
= 38.5 m2
APPEARS IN
संबंधित प्रश्न
A lawn is in the form of a rectangle whose sides are in the ratio 5 : 3. The area of the lawn is `3375m^2` . Find the cost of fencing the lawn at ₹ 65 per metre.
A footpath of uniform width runs all around the inside of a rectangular field 54m long and 35 m wide. If the area of the path is `420m^2` , find the width of the path.
In the following figure, O is the centre of a circular arc and AOB is a straight line. Find the perimeter and the area of the shaded region correct to one decimal place. (Take π = 3.142)
The area of the largest triangle that can be inscribed in a semi-circle of radius r, is
A square is inscribed in a circle. Find the ratio of the areas of the circle and the square.
In the given figure, ABCD is a rectangle inscribed in a circle having length 8 cm and breadth 6 cm. If π = 3.14, then the area of the shaded region is:
The given figures show a rectangle ABCD inscribed in a circle as shown alongside.
If AB = 28 cm and BC = 21 cm, find the area of the shaded portion of the given figure.
Two circles touch each other externally. The sum of their areas is 74π cm2 and the distance between their centers is 12 cm. Find the diameters of the circle.
Calculate the area of the shotput circle whose radius is 2.135 m.
Find the length of the rope by which a bull must be tethered in order that it may be able to graze an area of 2464 m2
