document.write( "Question 343254: I do not know how to go about solving this problem. \"You drive to the city at an average speed of 40km/h and return at an average speed of 60km/h. Find your average speed for the entire trip? Explain why the answer is not 50km/h\"
\n" ); document.write( "when i read the problem i assumed the answer was 50km/h because that was the average between the two. But after i read the last sentence, it changed my view on how to solve the problem. I need help on the process to answer the problem. \n" ); document.write( "

Algebra.Com's Answer #245603 by mananth(16946) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"+speed+=+distance+%2F+time\"$
\n" ); document.write( "..
\n" ); document.write( "you will see that speed is a function of time and distance.
\n" ); document.write( "speed varies with time, distance being same.
\n" ); document.write( "..
\n" ); document.write( "In the problem the distance is same but the time taken is different.
\n" ); document.write( "..
\n" ); document.write( "If the city was 120 miles
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\n" ); document.write( "time going will be 120/40 = 3hours
\n" ); document.write( "time returning = 120/60 = 2hours
\n" ); document.write( "Total 5 hours.
\n" ); document.write( "..
\n" ); document.write( "Distance is 240
\n" ); document.write( "time = 5
\n" ); document.write( "speed = 240/5
\n" ); document.write( "speed = 48 mph is the average speed \n" ); document.write( "

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