Advertisements
Advertisements
प्रश्न
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.
उत्तर
Let the area of the resulting circle be r.
π x (16)2 + π x ( 12 )2 = π x r2
256 π + 144 π = π x r2
400π = π x r2
r2 = 400
r = 20 cm
Hence the radius of the resulting circle is 20cm.
APPEARS IN
संबंधित प्रश्न
The length of a rectangular park is twice its breadth and its perimeter is 840 m. Find the area of the park.
The dimensions of a room are 14 m x 10 m x 6.5 m There are two doors and 4 windows in the room. Each door measures 2.5 m x 1.2 m and each window measures 1.5 m x 1 m. Find the cost of painting the four walls of the room at ₹ `35perm^2` .
The cost of painting the four walls of a room 12 m long at `₹ 30 per m^2 is ₹ 7560 per m^2` and the cost of covering the floor with the mat at ₹` 25 per m^2 is ₹ 2700 `. find the dimensions of the room.
A calf is tied with a rope of length 6 m at the corner of a square grassy lawn of side 20 m . If the length of the rope is increased by 5.5 m , find the increase in area of the grassy lawn in which the calf can graze .
Two circular pieces of equal radii and maximum area, touching each other are cut out from a rectangular card board of dimensions 14 cm × 7 cm. Find the area of the remaining card board. (Use π = 22/7).
What is the area of a sector of a circle of radius 5 cm formed by an arc of length 3.5 cm?
Write the formula for the area of a segment in a circle of radius r given that the sector angle is \[\theta\] (in degrees).
The hour hand of a clock is 6 cm long. The area swept by it between 11.20 am and 11.55 am is
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:
Find the area of a ring-shaped region enclosed between two concentric circles of radii 20 cm and 15 cm.