Advertisements
Advertisements
प्रश्न
A wire, when bent in the form of a square; encloses an area of 196 cm2. If the same wire is bent to form a circle; find the area of the circle.
Advertisements
उत्तर
Area of Square = 196 cm2
Side of Square = `sqrt("Area")` = `sqrt(196)` = 14 cm
Perimeter of Square = 4 x 14 cm
i.e. length of wire = 56 cm
Circumference of circle = 56 cm
2πr = 56
`2 xx 22/7 xx r = 56`
`r = (56 xx 7)/(2 xx 22)`
`r = 98/11` cm
`therefore "Area of circle enclosed" = pir^2`
= `22/7 xx 98/11 xx 98/11`
= `2744/11`
= 249.45 cm2
APPEARS IN
संबंधित प्रश्न
A room 4.9 m long and 3.5 m board is covered with carpet, leaving an uncovered margin of 25 cm all around the room. If the breadth of the carpet is 80 cm, find its cost at ₹ 80 per metre.
From each of the two opposite corners of a square of side 8 cm, a quadrant of a circle of radius 1.4 cm is cut. Another circle of radius 4.2 cm is also cut from the centre as shown in the following figure. Find the area of the remaining (Shaded) portion of the square. (Use π = 22/7)
In a hospital used water is collected in a cylindrical tank of diameter 2 m and height 5 m. After recycling, this water is used to irrigate a park of hospital whose length is 25 m and breadth is 20 m. If tank is filled completely then what will be the height of standing water used for irrigating the park.
An arc subtends an angle of 90° at the centre of the circle of the radius 14 cm. Write the area of minor sector thus formed in terms of π.
Find the area of sector of circle of radius 21 cm and central angle 1200.
A chord of a circle of radius 14 cm makes a right angle at the centre. Find the area of the sector.
The diameters of two circles are 32 cm and 24 cm. Find the radius of the circle having its area equal to the sum of the areas of the two given circles.
The diameter of a wheel is 0.70 m. Find the distance covered by it in 500 revolutions. If the wheel takes 5 minutes to make 500 revolutions; find its speed in :
(i) m/s
(ii) km/hr.
Calculate the area of the shotput circle whose radius is 2.135 m.
Find the area of the shaded region:
