document.write( "Question 1091568: Time varies inversely with speed if the distance is constant. A trip takes 4 hours at 80 km/h. How long does it take at 64 km/h?\r
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Algebra.Com's Answer #705984 by math_helper(2461)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "d = r * t    where r=rate, t=time, d=distance\r\n" );
document.write( "so yes, rearranging to t = d/r \"time varies inversely with speed if distance is constant\"\r\n" );
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document.write( "The trip is the same distance, no matter what the speed.  Can we find the trip distance?  Yes, from the speed and time information given (4 hrs at 80km/hr):  \r\n" );
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document.write( "d = 4hrs * 80km/hr = 320km\r\n" );
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document.write( "Now we can divide the trip distance by the other speed in order to get the time required:\r\n" );
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document.write( "t = 320km / 64km/hr = \"+highlight%285%29+\" hrs\r\n" );
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document.write( "A 2nd way to do this (although mathematically equivalent) is to use the ratio of the two speeds, essentially it is just a re-grouping the distance calculation, as follows:\r\n" );
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document.write( " t = (4hrs * 80km/hr) / 64km/hr = 4hrs * (80km/hr / 64km/hr)  = 4hrs * (1.25) = 5 hrs\r\n" );
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