Given the following information about the speed of light:
Speed of light in vacuum which has a refractive index of 1 is 300Km/sec
Speed of light in water which has a refractive index of 1.3 is 225Km/sec
Speed of light in diamond which has a refractive index of 2.4 is 125Km/sec

Estimate the speed of light in glass which has a refractive index of 1.5