A steam turbine operates on re-generative vapour power cycle, with one closed feed water heater receives some quantity of steam at intermediate pressure, develops a net power of 32000 kW. The steam generator supplies 44.08 kg/sec of steam at 7 MPa and 450C. The condenser functions at a vacuum pressure of 0.03 MPa. The turbine produces 731.89 kJ of work per kg of steam. The isentropic efficiencies of turbine and pump are 82% and 85 % respectively. Determine the fraction of steam supplied to feed water heater.