自行车=(617.5km/6.5h) X [6/(6+13)]=30km/h摩托车=(617.5km/6.5h) X [13/(6+13)]=65km/h
6:13=s1:s2s1=6/19*617.5=195s2=13/19*617.5=422.5195/6.5=30422.5/6.5=65
自行车:(617.5除以6.5)乘以十九分之六=35KM摩托:(617.5除以6.5)乘以十九分之十三=60KM