A person travels from X to Y at a speed of 30 km/hr and returns from Y to X by…
2024
A person travels from X to Y at a speed of 30 km/hr and returns from Y to X by increasing his speed by 50%. His average speed during the journey is :
- A.
37.5 km/hr
- B.
37 km/hr
- C.
36 km/hr
- D.
38 km/hr
Attempted by 8 students.
Show answer & explanation
Correct answer: C
First, determine the return speed. Increasing 30 km/hr by 50% results in 45 km/hr. Since the distance traveled is equal for both legs of the journey, use the harmonic mean formula for average speed: (2 * v1 * v2) / (v1 + v2). Substituting the values: (2 * 30 * 45) / (30 + 45) = 2700 / 75 = 36 km/hr.