The volume of a cone of height 3cm is 38\(\frac{1}{2}\)cm³. Find the radius of its base. [Take \(\pi = \frac{22}{7}\)]

3.0cm

3.5cm

4.0cm

4.5cm

Correct answer is B

Using V = \(\frac{3}{1} \pi r^2h\),

so, 38\(\frac{1}{2} = \frac{1}{3} \times \frac{22}{7} \times r^2 \times 3\)

\(\frac{77}{2} = \frac{22}{7} \times r^2\)

r² = \(\frac{77 \times 7}{2 \times 22}\)

r² = \(\frac{49}{4}\)

Hence, r = \(\sqrt{\frac{49}{4}}\)

= 3\(\frac{1}{2}\)

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The volume of a cone of height 3cm is 38\(\frac{1}{2}\)cm3. Find the radius of its base. [Take \(\pi = \frac{22}{7}\)]

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The volume of a cone of height 3cm is 38\(\frac{1}{2}\)cm³. Find the radius of its base. [Take \(\pi = \frac{22}{7}\)]