A boiler produces steam at a rate of 10/9 kg per second at 20 bar and 400°C. The efficiency of the boiler is 80%, and the feed-water temperature is 50°C. The calorific value of the fuel used is 44500 kJ/kg. Enthalpy of steam at 20 bar and 400°C is 3245.5 kJ/kg, and enthalpy of feed-water at 50°C is 209.3 kJ/kg. The fuel burning rate in kg/h is: