Lets get this :)
Volume(big cylinder) = [tex] \pi r^2h[/tex]
2187 = [tex] \pi r^2(3)[/tex]
[tex] \frac{2187}{3} = \pi r^2 [/tex]
729 = [tex] \pi r^2[/tex]
[tex] \frac{729}{ \pi } = r^2[/tex]
r = [tex] \sqrt{ \frac{729}{ \pi } } [/tex]
r ≈ 15.2 cm (radius of big cylinder)
The ratio of big cylinder to small one is:
3 : 1
Therefore, the big cylinder is 3 times bigger than the small cylinder
[tex] \frac{15.2}{3} [/tex] = r
r = 5.1 cm (radius of small cylinder)
V(small cylinder) = [tex] \pi (5.1)^2(1)[/tex]
= 81 cm³
Your answer is C. 81 cm³
