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#1 2008-08-27 10:48:12

tony123
Member
Registered: 2007-08-03
Posts: 229

what is the speed

when I take my dog for a walk," said a mathematical friend, "he frequently supplies me with some interesting puzzle to solve. One day, for example, he waited, as I left the door, to see which way I should go, and when I started he raced along to the end of the road, immediately returning to me; again racing to the end of the road and again returning. He did this four times in all, at a uniform speed, and then ran at my side the remaining distance, which according to my paces measured 27 yards. I afterwards measured the distance from my door to the end of the road and found it to be 625 feet. Now, if I walk 4 miles per hour, what is the speed of my dog when racing to and fro?"

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#2 2008-09-01 11:57:16

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: what is the speed

ohh that's an old Dudeney puzzle. I've never used the british metric system, but the simple answer is hidden in some algebraic properties of the given distances. (I'm not going to reveal more now, maybe someone might want to try it)


IPBLE:  Increasing Performance By Lowering Expectations.

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