A three-phase, three winding $\Delta / \Delta / Y (1.1kV/6.6kV/400V)$ transformer is energized from $AC$ mains at the $1.1kV$ side. It supplies $900kVA$ load at $0.8$ power factor lag from the $6.6kV$ winding and $300kVA$ load at $0.6$ power factor lag from the $400V$ winding. The $RMS$ line current in ampere drawn by the $1.1kV$ winding from the mains is ________. (Give the answer up to one decimal place.)