设乘客坐车行驶了x公里,根据题意得:8+(8-3)×1.4+(x-8)×2.1=44.4 8+7+2.1x-16.8=44.4, 2.1x-1.8=44.4, 2.1x=46.2, x=22,答:此乘客乘该出租车行驶的路程为22千米.