Advertisements
Advertisements
प्रश्न
Find the radius and area of the circle which has circumference equal to the sum of circumferences of the two circles of radii 3 cm and 4 cm respectively.
Advertisements
उत्तर
Let R be the radius of the big circle.
The radii of two circles are r1 = 3cm and r2 = 4cm
Now,
Circumference of big circle
= Sum of circumference of circles of radii r1 and r2
⇒ 2πR = 2πr1 + 2πr2
⇒ R = r1 + r2
⇒ R
= 3 + 4
= 7cm
∴ Area of big circle
= πR2 = `(22)/(7) xx 7 xx 7`
= 154cm2.
APPEARS IN
संबंधित प्रश्न
Given figure depicts an archery target marked with its five scoring areas from the centre outwards as Gold, Red, Blue, Black and White. The diameter of the region representing Gold score is 21 cm and each of the other bands is 10.5 cm wide. Find the area of each of the five scoring regions. [use π = 22/7]
The base of a right – angled triangle measures 48 cm and its hypotenuse measures 50 cm. Find the area of the triangle.
In the given figure, ABCD is a square of side 4 cm. A quadrant of a circle of radius 1 cm is drawn at each vertex of the square and a circle of diameter 2 cm is also drawn. Find the area of the shaded region. [π = 3.14]
In the given figure, the shape of the top of a table is that of a sector of a circle with centre O and ∠AOB = 90°. If AO = OB = 42 cm,· then find the perimeter of the top of the table.
Find the volume and the surface area of the spheres in the following :
Diameter= 6.3 cm
Find the radius of the circle whose circumference is equal to the sum of the circumferences of the circles having radius 15 cm and 8 cm.
Find the diameter of a circle whose circumference is equal to the sum of circumference of circles with radius 10 cm, 12 cm, and 18 cm.
The area between the circumference of two concentric circles is 2464cm2. If the inner circle has a circumference of 132cm, calculate the radius of the outer circle.
Circumference of a circle disc is 88 cm. Its radius is ______.
Circumference ‘C’ of a circle is equal to 2π × ______.
