A cone of radius 9 cm and height 15 cm is melted and made into a cylinder of height 45 cm. The diameter of the cylinder is:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 6 cm
According to the question
The volume of the cone = the volume of the cylinder
(1/3)πr2h = πR2H
where, r = radius of cone, h = height of cone, R = radius of cylinder, H = height of cylinder
(1/3) × 92 × 15 = R2 × 45
R = 3 cm
Hence, the diameter of the cylinder = 2 × 3 = 6 cm