Pawan travels from X to Y at the speed of 10 km/h, from Y to Z at 15 km/h and from Z to W at 20 km/h. If XY = YZ = ZW (in km), then the average speed of Pawan for the whole journey is:
1
\(13\frac{9}{13}\) km/h
2
\(13\frac{10}{13}\) km/h
3
\(13\frac{8}{13}\) km/h
4
\(13\frac{11}{13}\) km/h