A person travels from P to Q at a speed of 50 km/h and returns by increasing his speed by 60%. What is his average speed for both the trips?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 61.53 km/h
Formula used:
Average speed = Total distance/total time ---- (1)
Calculations:
Let the distance from P to Q be 50 km
Hence total distance = 100 km
Time taken from P to Q = 50/50 = 1 h
Increased speed = 160% of 50 = 80 km/h
Time taken from Q to P = 50/80 = 5/8 h
Using equation (1), we get
⇒ Average speed = 100/(1 + 5/8) = 800/13
⇒ 61.53 km/h