Question

从甲地到乙地有一段平路丶上坡路和下坡路,全程142km.汽车从甲地开往乙地,在平路每小时行30km

Answer 1

设从甲地到乙地上坡路X千米,下坡路Y千米,根据题意得：

X/28+(142-X-Y)/30+Y/35=4.5

X/35+(142-X-Y)+Y/28=4.7,

解得：X=42,Y=70.