The taxi charges in our area are as follows: the minimum rental is 3 kilometers, and the minimum rental amount is 5 yuan. If it exceeds 3 kilometers, 1.8 yuan will be charged per kilometer for the excess part (if it is less than 1 kilometer, it will be counted as 1 kilometer). If Yang Liu paid a total of 10.40 yuan for a taxi ride, how far did she travel at least? (results kept to 0.1 km)?
我区出租车是这样收费的：3千米起租，起租金额5元．超过3千米的，超过部分每千米加收1.8元(不足1千米的算1千米)．若一次杨柳同学乘出租车共付10.40元，那么她至少乘了多远的路程？(结果保留到0.1千米)？
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