Light will pass faster or slower through a substance with a refractive index of 2 than one with a refractive?

Question

Light will pass faster or slower through a substance with a refractive index of 2 than one with a refractive index of 3?

Answer 1

The higher the refractive index, the slower light travels through it.

So with a refractive index of 2-:

3 x 10^8 / 2 = 1.5 x 10^8

For 3-:
3 x 10^8 / 3 = 1 x 10^8

i.e. light travels faster through an R.I. of 2 than an R.I. of 3