Quantitative Aptitude Ques 1681
Question: Weight of a solid metallic sphere of radius 4 cm is 4 kg. The weight of a hollow sphere made with same metal, whose outer diameter is 16 cm and inner diameter is 12 cm, is
Options:
A) 20.5 kg
B) 15.5 kg
C) 16.5 kg
D) 18.5 kg
Show Answer
Answer:
Correct Answer: D
Solution:
- Volume of solid sphere of radius $ 4cm=\frac{4}{3}\pi {{(4)}^{3}}cm $ Volume of hollow sphere $ =\frac{4}{3}\pi [{{(8)}^{3}}-{{(6)}^{3}}]cm^{3} $ $ \because $ Weight of $ \frac{4}{3}\pi {{(4)}^{3}}cm^{3}=4kg $
$ \therefore $ Weight of $ \frac{4}{3}\pi [{{(8)}^{3}}-{{(6)}^{3}}]cm^{3} $ $ =\frac{4}{\frac{4}{3}\pi {{(4)}^{3}}}\cdot \frac{4}{3}\pi [{{(8)}^{3}}-{{(6)}^{3}}] $ $ =\frac{4(512-216)}{4^{3}}=18.5kg $
BETA
