Time taken to reach the bottom of inclined plane.
$\sqrt{\frac{2l\Bigg(1+\frac{K^2}{R^2}\Bigg)}{g\, sin\, \theta}}$
Here, l is length of incline plane
For solid cylinder $K^2=\frac{R^2}{2}$
For hollow cylinder$K^2=R^2$
Hence, solid cylinder will reach the bottom first.
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