SSC CGL 2020 PYQ — Question 23

SSC CGL Tier II - Quant - 18 Nov 2020 • Quantitative Aptitude • Q23

The number of lead balls, each 3 cm in diameter , that can be made from a solid lead sphere of diameter 42 cm is:

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e. 2744

Radius of sphere = 42/2 = 21cm.

The radius of a lead ball = 3/2

In this case, volume remains the same,

The volume of the sphere = volume of n lead balls

4/3 × π\pi × 21 × 21 × 21 = n × 4/3 × π\pi × 3/2 × 3/2 × 3/2

n = 2744.