Question

An object is folloeing on the surface of water with a layer of oil 50% of the object's volume is in water , 30% is in oil, ands the rest is above the surface of oil. if oil's density is 0,8 g/〖cm〗^3, then the object's density is...in g/〖cm〗^3

Answer 1

I think you can consider the oil-water system as a single liquid of a density which is the average of the densities of water and oil.
Now, in this single liquid, 80% of the object's volume is immersed. Now, find the object's density.
Hint: The buoyant force experienced by the object is equal to its weight.
Can you write down the expression for the buoyant weight?