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
In the following figure, from a rectangular region ABCD with AB = 20 cm, a right triangle AED with AE = 9 cm and DE = 12 cm, is cut off. On the other end, taking BC as diameter, a semicircle is added on outside' the region. Find the area of the shaded region. [Use π =]`22/7` [CBSE 2014]
In the following figure, OE = 20 cm. In sector OSFT, square OEFG is inscribed. Find the area of the shaded region.
In the following figure, AB and CD are two diameters of a circle perpendicular to each other and OD is the diameter of the smaller circle. If OA = 7 cm, find the area of the shaded region.
In the following figure, ABCD is a trapezium of area 24.5 cm2 , If AD || BC, ∠DAB = 90°, AD = 10 cm, BC = 4 cm and ABE is quadrant of a circle, then find the area of the shaded region. [CBSE 2014]
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:
If the radius of a circle is doubled, its area becomes ____________.
In figure, a square of diagonal 8 cm is inscribed in a circle. Find the area of the shaded region.
Area of a rectangle and the area of a circle are equal. If the dimensions of the rectangle are 14 cm × 11 cm, then radius of the circle is ______.
If radius of a circle is increased to twice its original length, how much will the area of the circle increase?
