Answer: D
Let the heights be \(h_1\) and \(h_2\), and the base radii be \(4r\) and \(5r\) respectively.
\(∴ \cfrac{1}{3} π(4r)^2 h_1 : \cfrac{1}{3} π(5r)^2 h_2 = 1:4\)
or, \(16r^2 h_1 : 25r^2 h_2 = 1:4\)
or, \(\cfrac{16h_1}{25h_2} = \cfrac{1}{4}\)
or, \(\cfrac{h_1}{h_2} = \cfrac{25}{64}\)
or, \(h_1:h_2 = 25:64\).
So, the ratio of their heights is 25:64.
Let the heights be \(h_1\) and \(h_2\), and the base radii be \(4r\) and \(5r\) respectively.
\(∴ \cfrac{1}{3} π(4r)^2 h_1 : \cfrac{1}{3} π(5r)^2 h_2 = 1:4\)
or, \(16r^2 h_1 : 25r^2 h_2 = 1:4\)
or, \(\cfrac{16h_1}{25h_2} = \cfrac{1}{4}\)
or, \(\cfrac{h_1}{h_2} = \cfrac{25}{64}\)
or, \(h_1:h_2 = 25:64\).
So, the ratio of their heights is 25:64.