If a wood is drowned in water up to 2/3 of its volume and the same wood is dipped in a oil upto 9/10 of its volume. What's the density of wood and the relative oil?

Density of water - 1000kgm-3

S. G. or specific gravity is the ratio of the density of an object to a fluid. It also is the fraction of the object's volume that would be submerged if the object were placed in the fluid. (note: if S. G.>1, the object will sink)

S. G. = density (wood) / density (water)

2/3 = density (wood) / 1000

density (wood) = 2000/3 kg/m^3 = ~666.67 kg/m^3

S. G. = density (wood) / density (oil)

9/10 = 2000/3 / density (oil)

density (oil) = 2000/3 / 9/10 = 20000/27 kg/m^3 = ~740.74 kg/m^3