SOLUTION: If you bike for 2 hours at 30km/h and for 2 hours at 20 km/h, what is your average speed for the whole trip?

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Question 525907: If you bike for 2 hours at 30km/h and for 2 hours at 20 km/h, what is your average speed for the whole trip?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If you bike for 2 hours at 30km/h and for 2 hours at 20 km/h, what is your average speed for the whole trip?
:
Find the total distance of the trip: (2*30) + (2*20) = 100 km
:
let a = the average speed for the whole trip
:
Write time time equation, time = dist/speed
60%2F30 + 40%2F20 = 100%2Fa
2 + 2 = 100%2Fa
4 = 100%2Fa
4a = 100
a = 25 km/hr