```Date: Oct 26, 1999 1:13 PM
Author: Kresimir Kumericki
Subject: Flies, trains, and series summation

[sci.physics.research removed]In sci.physics Chris Hillman <hillman@math.washington.edu> wrote:> On 22 Oct 1999, Phillip Helbig wrote:>> The problem being: Two trains are 60 miles apart and approaching each>> other at 30 miles per hour.  There is a fly flying between the>> cowcatchers of each train, at 60 miles per hour, back and forth, turning>> around immediately.  What is the total distance covered by the fly> The problem you mention certainly strikes me as much too simple to have> the ring of truth, since anyone could sum -that- series in their head in a> few seconds!Then, "ian" <walkersystems@one.net.au> wrote:> why sum a series?> it takes the trains 1 hour to hit, the fly travels at 60 m/hr so the fly> flies 60 miles...  When I heard about this puzzle long time ago I got the ideathat perhaps this way you can sum some complicated series usingthe following procedure:  Construct (complicated) trains-fly path such that the fly, flying toand fro, travels distances equal to the terms of your series.Than the distance traveled by train(s) equals the sum of the series.  Now, I was too lazy (and mathematically ignorant) to investigateinto this idea but I'd love to hear if this wouldn't work and why (too trivial probably).-- -------------------------------------------------------------Kresimir Kumericki  kkumer@phy.hr  http://www.phy.hr/~kkumer/Theoretical Physics Department, University of Zagreb, Croatia-------------------------------------------------------------
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