arrow
arrow
arrow
The ratio of the heights of a right circular cone and a right circular cylinder is 2 : 9 and the ratio of the radii of their bases is 7 : 2. If the vo
Question

The ratio of the heights of a right circular cone and a right circular cylinder is 2 : 9 and the ratio of the radii of their bases is 7 : 2. If the volume of the cylinder is 972 cm³ , then the volume (in cm³ ) of the cone is:

A.

891

B.

885

C.

889

D.

882

Correct option is D

Given:
Ratio of height of cone (h1h_1​) to cylinder (h2h_2​) = 2 : 9
Ratio of radius of cone (r1r_1​) to cylinder (r2r_2​) = 7 : 2
Volume of cylinder = 972 cm³

Formula Used:
Volume of cylinder = πr2h \pi r^2 h​​
Volume of cone = 13πr2h\frac{1}{3} \pi r^2 h​​

Solution:
Let h1h_1​ = 2h and h2h_2​ = 9h.
Let r1r_1​ = 7r and r2r_2​ = 2r.
Volume of cylinder = π×(2r)2×9h=36πr2h\pi × (2r)^2 × 9h = 36\pi r^2 h​​
It is given that 36πr2h=97236\pi r^2 h = 972​​
πr2h=97236=27\pi r^2 h = \frac{972}{36} = 27​​
Volume of cone = 13π×(7r)2×2h\frac{1}{3} \pi × (7r)^2 × 2h​​

Volume of cone = 13π×49r2×2h=983πr2h\frac{1}{3} \pi × 49r^2 × 2h = \frac{98}{3} \pi r^2 h​​
Substitute the value of πr2h=27\pi r^2 h = 27​:
Volume of cone = 983×27\frac{98}{3} × 27​​
Volume of cone = 98 × 9 = 882 cm³

Final Answer
So the correct answer is (d)

Free Tests

Free
Must Attempt

RRB NTPC UG Level PYP (Held on 7 Aug 2025 S1)

languageIcon English
  • pdpQsnIcon100 Questions
  • pdpsheetsIcon100 Marks
  • timerIcon90 Mins
languageIcon English
Free
Must Attempt

CBT-1 Full Mock Test 1

languageIcon English
  • pdpQsnIcon100 Questions
  • pdpsheetsIcon100 Marks
  • timerIcon90 Mins
languageIcon English
Free
Must Attempt

RRB Group D Full Mock Test 1

languageIcon English
  • pdpQsnIcon100 Questions
  • pdpsheetsIcon100 Marks
  • timerIcon90 Mins
languageIcon English

Similar Questions

test-prime-package

Access ‘RRB Section Controller’ Mock Tests with

  • 60000+ Mocks and Previous Year Papers
  • Unlimited Re-Attempts
  • Personalised Report Card
  • 500% Refund on Final Selection
  • Largest Community
students-icon
530k+ students have already unlocked exclusive benefits with Test Prime!

Similar Questions

Our Plans
Monthsup-arrow