A boiler produces 4 kg of steam per kg of coal burnt. The feed water enters at 45 °C. The steam is generated at 10.5 bar with a dryness fraction of 0.98 (at 10.5 bar: h_{f} = 772 kJ/kg, h_{fg} = 2006 kJ/kg; take h_{fw} ≈ 4.187 × t and latent heat at 100 °C = 2257 kJ/kg). Determine the equivalent evaporation from and at 100 °C per kg of coal (answer in kg per kg of coal).