# Average speed

alex engler
If the average speed going to town is 40km/hr, and return at an average speed of 60 km/hr. what is the average speed? why is it not 50 km/hr

Is the answer 30? because he goes 40 km/hr for 1 1/2 hours. etc.

You are correct that the "average speed" is not the arithetic average ($\frac{v_1+v_2}{2}$) but any "average" of two numbers has to be between them!