Abdul, while driving to school, computes the average speed for his trip to be 20km h−1. On his return trip along the same route, there is less traffic and the average speed is 30km h−1. What is the average speed for Abdul's trip?
Let us assume that Abdul is travelling x kilometer distance while going to school.Distance = Speed x Time
1)When it's average speed is 20 km/hr
x=v1×t1=20×t1
2)When it's average speed is 30 km/hr
x=v2×t2=30×t2
Vaverage=totaldistancetravelledtotaltimetaken
Vaverage=x+xxv1+xv2=2xx20+x30=24 km h−1