question_answer 3)

Abdul, while driving to school, computes the average speed for his trip to be 20 km On his return trip along the same route, there is less traffic and the average speed is 40 km What is the average speed for Abdul?s trip?

Answer:

Let the school be at a distance of  km. If  is time taken to reach the school, then If is time taken to reach back, then total time, total time, Average speed