A man travelled by car from city A to city B at a speed of 24 km/h and returned from city B to city A at 16 km/h. Find his average speed over the whole journey.
Answer & explanation
Correct answer: option 4
Average Speed = \(\frac{ 2 × S1 × S2}{S1 + S2}\)
S1 = 24 km/h & S2 = 16 km/h is given
Average Speed = \(\frac{ 2 × 16 × 24}{16 + 24}\)
= \(\frac{ 768}{40}\)
= 19.2 km/h
Average speed = 19.2 km/h