Question

Ram while driving to school has an average speed of 20 km/h. While returning from his school his average speed is 30 km/h. What is his average speed for the whole path or journey ?

Answer 1

Your answer is 50km/h

Answer 2

average speed=total distance/total time
when he was going to school x km far from his home,time taken=x/20hrs
coming from school, time taken=x/30
so average speed=
$\frac{x}{ \frac{x}{20} + \frac{x}{30} } = \frac{60x}{3x + 2x} = \frac{60}{5} = 12kmph$