The curved surface area of the sphere is 154 cm2. Find the volume of the sphere (rounded off to one digit after decimal).
Answer & explanation
Correct answer: option 2
We know that,
Surface area of a sphere = 4πr2
Volume of a sphere = \(\frac{4}{3}\)πr3
The curved surface area of the sphere is 154 cm2
4πr2 = 154
= 4 × \(\frac{22}{7}\) × r2 = 154
= r2 = \(\frac{49}{4}\)
= r = \(\frac{7}{2}\)
So, volume = \(\frac{4}{3}\) × \(\frac{22}{7}\) × (\(\frac{7}{2}\))3
= \(\frac{4}{3}\) × 22 × \(\frac{49}{8}\) = \(\frac{539}{3}\) = 179.7