Azeotrope-like compositions are disclosed. The azeotrope-like compositions are mixtures of HFO-E-1,3,4,4,4-Pentafluoro-3-trifluoromethyl-1-butene and E-1-Chloro-3,3,3-trifluoropropene. Also disclosed is a process of preparing a thermoplastic or thermoset foam by using such azeotrope-like compositions as blowing agents. Also disclosed is a process of producing refrigeration by using such azeotrope-like compositions. Also disclosed is a process of using such azeotrope-like compositions as solvents. Also disclosed is a process of producing an aerosol product by using such azeotrope-like compositions. Also disclosed is a process of using such azeotrope-like compositions as heat transfer media. Also disclosed is a process of extinguishing or suppressing a fire by using such azeotrope-like compositions. Also disclosed is a process of using such azeotrope-like compositions as dielectrics.