Advertisements
Advertisements
प्रश्न
Find the area of the circle, length of whose circumference is equal to the sum of the lengths of the circumferences with radii 15 cm and 13 cm.
Advertisements
उत्तर
In a circle
Circumference = Sum of circumferences of two circle of radii 15 cm and 13 cm
Now circumference of first smaller circle = 2πr
= `2 xx 22/7 xx 15 = 660/7` cm
Circumference of the second smaller circle
= `2 xx 22/7 xx 13 = 572/7` cm
∴ Circumference of the bigger circle
= `660/7 + 572/7 = 1232/7` cm
Let R be its radius, then
`2pi"R" = 1232/7 ⇒ (2 xx 22)/7 "R" = 1232/7`
⇒ R = `1232/7 xx 7/44 = 28` cm
∴ Area of the circle = `pi"R"^2`
= `22/7 xx 28 xx 28 "cm"^2 = 2464` cm2
APPEARS IN
संबंधित प्रश्न
The area of sector is one-twelfth that of the complete circle. Find the angle of the sector .
In the following figure, ABC is a right-angled triangle, ∠B = 90°, AB = 28 cm and BC = 21 cm. With AC as diameter a semicircle is drawn and with BC as radius a quarter circle is drawn. Find the area of the shaded region correct to two decimal places.
Find the area of sector of circle of radius 21 cm and central angle 1200.
The area of a circular path of uniform width h surrounding a circular region of radius r is
The radius of a circle is 20 cm. It is divided into four parts of equal area by drawing three concentric circles inside it. Then, the radius of the largest of three concentric circles drawn is
What is the diameter of a circle whose area is equal to the sum of the areas of two circles of diameters 10 cm and 24 cm?
The area of circle is equal to the sum of the areas of two circles of radii 24 cm and 7 cm. The diameter of the new circle is
A chord of a circle of radius 10 cm subtends a right angle at the centre. The area of the minor segments (given, π = 3.14) is
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 ______.
A table top is semicircular in shape with diameter 2.8 m. Area of this table top is ______.
