Correct Answer - Option 1 : 12.5 km/hr
Solution:
Given:
Average speed = 10 km/hr
Formula Used:
Average speed = Total distance traveled/Total time
Speed = distance/ Time
Calculations:
Let the distance traveled towards east direction be x km.
Total distance = (15 + x) km
Total Time = (2 + 2) hrs
Average speed = (15+x)/4 = 10
⇒ 15 + x = 40
⇒ x = 25 km
The distance traveled towards east direction = 25 km
Speed = 25/2 = 12.5 km/hr