Two cylindrical containers are filled

to the same depth with water.

The first container has a radius of 16 cm

and the water in it has a mass of 16 kg.

If the second container has a radius of 8 cm,

find the mass of the water inside it.

Once you know the volume of the displaced water, you can immediately determine its weight by multiplying by the density of water at the relevant temperature. That's because the definition of density (d) is mass (m) divided by volume (v), so m = dv.