Advertisements
Advertisements
Question
Find the circumference of the inner and the outer circles, shown in the adjoining figure? (Take π = 3.14)

Advertisements
Solution
Radius of outer circle = 19 m
Circumference = 2πr
= 2 × 3.14 × 19
= 119.32 m
Radius of inner circle = 19 − 10
= 9 m
Circumference = 2πr
= 2 × 3.14 × 9
= 56.52 m
APPEARS IN
RELATED QUESTIONS
A pendulum swings through an angle of 30º and describes an arc 8.8 cm in length. Find the length of the pendulum.
The minute hand of a clock is 10cm long. Find the area of the face of the clock described by the minute hand between 9 A.M. and 9.35 A.M.
The radius of a sector of a circle is 7 cm. If the measure of the arc of the sector is - three right angles; find the area of the sector in case.
The sum of the radii of two circles is 7 cm, and the difference of their circumferences is 8 cm. Find the circumference of the circles.
The inside perimeter of a running track shown in the figure is 400 m. The length of each of the straight portions is 90 m, and the ends are semicircles. If the track is 14 m wide everywhere, find the area of the track. Also, find the length of the outer boundary of the track.

A wire when bent in the form of a square encloses an area of 484 cm2. If the same wire is bent into the form of a circle, find the area of the circle.
Find the area enclosed between two concentric cirdes of radii 6.3 cm and 8.4 cm. A third concentric circle is drawn outside the 8.4 cm circle, so that the area enclosed between it and 8.4 cm cirde is the same as that between two inner circles. Find the radii of the third circle correct to two decimal places .
Find the area and perimeter of the following semicircles: Diameter = 7cm
The area of a circular playground is 22176 m2. Find the cost of fencing this ground at the rate of Rs 50 per metre.
A circular pond is 17.5 m is of diameter. It is surrounded by a 2 m wide path. Find the cost of constructing the path at the rate of Rs 25 per m2.
