A bottle has mass of 1.8 kilograms when its completly filled with juice.It hass a mass of 1.23 kilograms when 3/8 of juice is removed.What is the mass of the empty bottle.

answer:

mass of filled bottle = 1.8kg

mass 0f 3/8 juice = 1.8-1.23 = 0.57kg

total mass of juice = 0.57*8/3 = 1.52

mass of the empty bottle = 1.8-1.52 = 0.28kg