<PRE><B>Question 776152</B>
Having traveled 850 km in 6.00 h, how fast should a driver go if he is to finish the entire 1800 km journey at an average speed of 100 km/h?
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Time to average 100 km/h: 1800/100 = 18 hours
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Time remaining after 6 hours leg:: 12 hours
Distance remaining after 6 hour leg:: 1800-850 = 950 km
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Rate for 2nd leg of journey:: 950 km/12 hrs = 79.17 km/hr
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Cheers,
Stan H.</PRE>