P. 4508. The average speed of the tourists when they walk from the shelter house to the hilltop was 1.5 km/h, whilst on the way back it was 3.5 km/h. The average speed for the whole distance from the shelter house back to the shelter house was 2 km/h. What fraction of the total time of the excursion did the tourist spend on the hilltop having a rest?
Deadline expired on 11 March 2013.