SSC CGL 2018 PYQ — Question 41

SSC CGL Tier II Quant - 17/02/2018 • Quantitative Aptitude • Q41

Radius of base of a hollow cone is 8 cm and its height is 15 cm. A sphere of largest radius is put inside the cone. What is the ratio of the radius of base of cone to the radius of shpere ?

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 ie 5 : 3.

Radius of base of cone = 8 cm

Height = 15 cm

AM = 15

Let OM = r [radius of sphere]

In ΔAOD and ΔAMC

∠D = ∠M = 90°

∠A = common

So, ΔAOD ~ ΔAMC

Now, 17/(15 - r) = 8/r ; r = 24/5

Radius of cone/Radius of sphere = (8 × 5)/24

= 5 : 3