A man travels 50 km at speed 25 km/h and next 40 km at 20 km/ h and there after travels 90 km at 15 km/h. His average speed is :
A18 kmph.
B20 kmph.
C25 kmph.
D15 kmph.
Answer:
A. 18 kmph.
Read Explanation:
A man travels 50 km at 25 kmph
Time taken to travel 50 km = 50/25 = 2 hours
Next 40 km at 20 kmph
Time taken to travel 40 km = 40/20 = 2 hours
90 km at 15 kmph
Time taken to travel 90 km = 90/15 = 6 hours
Total distance = 180 km
Total time = 10 hour
Average speed = 180/10 = 18 km/hr