Given,
Total surface area of cylinder = 231 cm2
Curved surface area = \(\frac{2}{3}\) total surface area = \(\frac{2}{3}\) x 231 = 154 cm2
so,
= 2πrh = \(\frac{2}{3}\) 2πr(r + h)
= 3 h = 2h + 2r
= h = 2r.............(i)
And,
= 2πr(r + h) = 231
= 2 x \(\frac{22}{7}\) x r x 3r = 231(putting h = 2r)
= r2 = \(\frac{231\times 3\times 7}{44}\) = \(\frac{49}{4}\)
= r = \({\sqrt\frac{49}{4}}\) = \(\frac{7}{2}\) = 3.5 cm
= h = 2r = 2×3.5 = 7 cm
Volume of cylinder = πr2h = \(\frac{22}{7}\) x 3.5 x 3.5 x 7 = 269.5 cm3