Question

if the absolute refractive indices of Glass and water are 3/2 and 4/ 3 respectively what is the refractive index of Glass with respect to water

Answer 1

Absolute refractive index of glass be Xg=3/2.
Absolute refractive index of water be Xw=4/3.
Then the refractive index of glass wrt to air is
$\frac{xg}{xw} = \frac{ \frac{3}{2} }{ \frac{4}{3} } = \frac{3 \times 3}{4 \times 2} = \frac{9 }{8}$

Answer 2

Ugw=3/2/4/3=9/8. Well it is glass with respect to water so it is 9/8.