Ball here, Ball there

A uniform ball of radius $\text{R}$ started from rest and descended a vertical distance $\text{h}$ while rolling without slipping down a ramp. Then after it hit the ground, the experiment is again conducted but now, ramp is replaced by rails $d$ distance apart.

Find the ratio $\displaystyle {(\frac{{v}_{cm, ramp}}{{v}_{cm, rails}})}^{2}$ . If it can be written as $\frac{a}{b}$ , give your answer as $a + b$ .

Details

1. $R = 3 m, d = 2 m, h = 10 m, g = 9.8 m{s}^{-2}$

2. Friction and air resistance are not be considered.

3. ${v}_{cm, a}$ means velocity of the center of mass when 'a' is used.