SOLUTION: If you bike for 60km at 30km/h and return at 20km/h, what is your average speed for the whole trip?

Question 402077: If you bike for 60km at 30km/h and return at 20km/h, what is your average speed for the whole trip?
Found 2 solutions by robertb, amalm06:
Answer by robertb(5830) (Show Source): You can put this solution on YOUR website!
Use the harmonic mean:

Answer by amalm06(224) (Show Source): You can put this solution on YOUR website!
(1/20)(60)=3

(1/30)(60)=2

Average speed=(60+60)/5=24 km/hr
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