Question

Abdul, while driving to school, computes the average speed for
route, there is less traffic and the average speed is
his trip to be 20 km h-1. On his return trip along the same
30 km h-!. What is the average speed for Abdul's trip?
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Answer 1

Average speed is (20 + 30)/2 = 25 kmph

Answer 2

Answer:

Let the distance be =x

distance while going =distance while returning

time =distance /speed

so, the time while going =x/20

time while coming =x/30

total time =x/20+x/30

= (3x+2x)/60

=5x/60

=x/12

total distance =2x

average speed =total distance /total speed

2x*12/x

= 24 km/hr