VITEEE 2009 Paper

A piece of metal weighs 45g in air and 25g in a liquid of density 1.5×103‌kg−m−3 kept at 30°C. When the temperature of the liquid is raised to 40°C, the metal piece weights 27g. The density of liquid at 40°C is 1.25×103‌kg−m−3. The coefficient of linear expansion of metal is