What Is the Average Speed of a Motorist Traveling Different Speeds?

AI Thread Summary
To calculate the average speed of a motorist traveling 30 miles at 60 mph and 60 miles at 30 mph, the total distance is 90 miles. The total time taken is 0.5 hours for the first segment and 2 hours for the second, resulting in a total time of 2.5 hours. The average speed is then calculated by dividing the total distance by the total time, yielding an average speed of 36 miles per hour. The discussion also notes a previous thread that addressed this calculation method. The final average speed is confirmed to be 36 mph.
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Homework Statement



a motorist travels at 30 miles at 60 miles per hr, and then 60 miles at 30 miles per hr.

what is the average speed


Homework Equations





The Attempt at a Solution



I have tried to set this up and i get every answer, except 36 m/hr, can you please point me the equation set up! thanks.
 
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nevermind, i already posted this and i saw the thread on how to do it.

its the distance of 90, divided by .5 hrs + 2hrs which is 36 miles per hour.


sorry for the double post.
 

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