Question

Abdul, while driving to school the average speed for his trip to be 20 km h. On his return trip along the same route, there is less traffic and the average speed is 30km h. What is the average speed of Abdul's trip?
$v = u + at \\ s = ut + 1 \div 2at {}^{2} \\ 2as = v {}^{2} - u {}^{2}$

Answer 1

hope it helps.........

Answer 2

by Vavg=(V1+V2)/2 so answer is (20+30)/2=25kmph