<PRE><B>Question 601429</B>
a ski lift carried Paul up a slope at rate of 6 km/h, and he skied back down parallel to the lift at 34 km/h.  The round trip took 30 minutes.  How far did he ski and for how long???
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The average speed of the round trip is
2*6*34/(6+34) = 10.2 km/hr
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RT distance = 10.2*0.5 = 5.1 km
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2.55 km skiing
t = d/r = 2.55/34
= 0.075 hr or 4.5 minutes skiing
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