Abdul while driving to school computes the average speed of his trip to be 20kmh-1 on his return trip along the same route there is less traffic and the average speed is 40 kmh-1 what is average speed for Abdul trip
Answers
Answered by
13
Explanation:
Assume that the total distance covered by Abdul is x km.
Time = Distance/Speed
t1 = x/20 hr and t2 = x/40 hr
Average speed = Total distance/Total time taken
Total distance covered = x + x = 2x km
Total time taken = t1 + t2 = x/20 + x/40 = 3x/40
Average speed = 2x/(3x/40) = 26.67 km/hr
OR
Average speed = (2 × s1 × s2)/(s 1 + s2)
= (2 × 20 × 40)/(20 + 40)
= 1600/60
= 26.67 km/hr
Similar questions