A homogeneous earthen embankment has an upstream water level of \(12\) m. The top width of the embankment is \(3\) m, and its upstream and downstream slopes (horizontal:vertical) are \(2:1\) and \(2.5:1\), respectively. A freeboard of \(2\) m is provided. The coefficient of permeability of the fill material is \(2.5 \times 10^{-5}\) m/s. If a \(20\) m long horizontal filter is placed inward from the downstream toe, the seepage discharge per unit length of the embankment is \(n \times 10^{-5}\) m\(^3\)/s per m. The value of \(n\) is ________. (Rounded off to two decimal places)