Q. 244.3( 7 Votes )
Abdul, while driving to school, computes the average speed for his trip to be 20 km h-1. On his return trip along the same route, there is less traffic and the average speed is 30 km h-1. What is the average speed for Abdul’s trip?
Let us assume the school to be at distance x km from where Abdul starts
Suppose the time taken while driving to school is t1Given,
Average speed = 20 km/h
On returning from the trip the average speed is 30 km/hLet, the time taken for the return trip is t2
Now, total distance of the whole trip from going to trip to returning back to school is:Total distance = x + x
= 2x Km (3)Adding (1) and (2) to get the total time
Total Time taken = Time taken to go to college +Time taken to return back to school
Solving this equation
Now, we will calculate the average speed of the whole trip:Average speed =
= 24 km/h
Therefore, the average speed for Abdul’s whole trip from going from to school to return back is 24 Km/h.
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