wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

The diameters of two cones are equal. If their slant heights are in the ratio 5:4, then the ratio of their curved surface areas is

A
5:4
No worries! Weā€˜ve got your back. Try BYJUā€˜S free classes today!
B
16:25
No worries! Weā€˜ve got your back. Try BYJUā€˜S free classes today!
C
4:5
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution

The correct option is C 4:5
Given, diameters of two cones are equal.
We know that, diameter = radius2
Implies radii of the two cones are also equal
Given, the slant heights are in the ratio 5:4.
Let the slant height of 1st cone be l1 and slant height of 2nd cone be l2.

Curved surface area of the first cone =πrl1
Curved surface area of the second cone
=πrl2

Now, ratio of their curved surface areas
=πrl1πrl2=l1l2=54

So, the ratio of curved surface areas is 5:4.

flag
Suggest Corrections
thumbs-up
2
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Introduction - concept
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon