Quantitative Aptitude Ques 2086
Question: The volume of a solid hemisphere is $ 19404cm^{3}. $ Its total surface area is
Options:
A) $ 4158cm^{2} $
B) $ 2858cm^{2} $
C) $ 1738cm^{2} $
D) $ 2038cm^{2} $
Show Answer
Answer:
Correct Answer: A
Solution:
- Volume of hemisphere = 19404 $ \frac{2}{3}\pi r^{3}=19404 $
$ \Rightarrow $ $ \frac{2}{3}\times \frac{22}{7}\times r^{3}=19404 $
$ \Rightarrow $ $ r^{3}=\frac{19404\times 3\times 7}{2\times 22}=9261 $ $ r=\sqrt[3]{21\times 21\times 21}=21cm $
$ \therefore $ Total surface area $ =3\pi r^{2} $ $ =3\times \frac{22}{7}\times 21\times 21=4158cm^{2} $
BETA
