Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
For circle with radius = 15 cm
Circumference of circle = 2πr
= `2xx22/7xx15` cm
= `660/7` cm
For circle with radius = 8 cm
Circumference of circle = 2πr
= `2xx22/7xx8` cm
= `352/7` cm
Sum of the circumferences of these two circles
= `660/7"cm"+352/7"cm"=1012/7"cm"`
If the required radius = R cm
Its circumference = 2πR
= `2xx22/7xx"R cm"`
= `44/7"R cm"`
Given, `44/7"R"=1012/7`
⇒ R =`7/44xx1012/7` cm
= 23 cm
∴ Required radius = 23 cm
APPEARS IN
संबंधित प्रश्न
In Figure, find the area of the shaded region [Use π = 3.14]
Choose the correct alternative answer for the following question.
A cone was melted and cast into a cylinder of the same radius as that of the base of the cone. If the height of the cylinder is 5 cm, find the height of the cone.
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, find the area of the shaded region, if ABCD is a square of side 14 cm and APD and BPC are semicircles.

A chord of a circle of radius 30 cm makes an angle of 60° at the centre of the circle. Find the areas of the minor major segments.
Find the curved surface area , the total surface area and the volume of a cone if its :
Height = 16 cm , diameter = 24 cm
Find the area and perimeter of the following sector :
Radius= 4.2 cm, angle at the centre is 60 °
The radius of two circles are in the ratio 3 : 5, find the ratio between their circumferences.
The cost of fencing a circular field at the rate of Rs.250 per metre is Rs.55000. The field is to be ploughing at the rate of Rs.15 per m2. Find the cost of ploughing the field.
The area of a circular playground is 22176 m2. Find the cost of fencing this ground at the rate of Rs 50 per metre.
