Question

Inthe given figure a circular track is in the form of a ring whose inner circumference is 88cm and outer circumference is 132cm. Find its width

Answer 1

Solution:-
Let 'R' be the radius of the outer circular ring and 'r' be the radius of the inner circular ring.
Now, according to the question.
Circumference of a circle = 2πR
132 = 2*22/7*R
R = (132*7)/(22*2)
R = 21 cm 
Radius of the outer circular ring is 21 cm.
Circumference of inner circular ring = 88 cm
circumference = 2πr
88 = 2*22/7*r
r = (88*7)/(22*2)
r = 14 cm.
Now, width of the track = radius of the outer ring - radius of the inner ring
= 21 - 14 
= 7 cm
So, the width of the track is 7 cm.
Answer.

Answer 2

Answer:

Step-by-step explanation:

We have,

Height(h) = 24 cm and the circumferences of circular faces of a frustum = 132 cm and 88 cm.

We have,

⇒

⇒

⇒   cm

And,

⇒

⇒ cm

Slant height, l =

cm

∴  The curved surface area of the frustum

Hence, the curved surface area of the frustum 2750