document.write( "Question 1055299: Please help me.
\n" ); document.write( "Jenny is cycling up a hill at a constant speed of 15 km/h and returns down the hill at a constant speed of 35 km/h. Calculate the average speed of her whole trip.
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Algebra.Com's Answer #670531 by Alan3354(69443)\"\" \"About 
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Jenny is cycling up a hill at a constant speed of 15 km/h and returns down the hill at a constant speed of 35 km/h. Calculate the average speed of her whole trip.
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\n" ); document.write( "Avg speed of a round trip is similar to parallel resistors and parallel flow or work.
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\n" ); document.write( "Avg = 2*15*35/(15+35)
\n" ); document.write( "= 21 km/hr
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