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Guest Message by DevFuse


Member Since 18 Feb 2013
Offline Last Active May 26 2015 05:36 PM

#336564 Having sisters

Posted by BMAD on 10 November 2013 - 05:51 PM

Do men have more sisters then women?

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#336475 Grazing cows

Posted by BMAD on 04 November 2013 - 01:36 AM

Freddie the farmer has a paddock that he uses to graze his stock of cows. Each cow eats the same amount of grass each day, regardless of how many other cows are in the paddock and irrespective of the amount of grass left in the paddock. In an experiment, Freddie puts 6 cows into the paddock and he finds out it takes 3 days for them to eat all the grass. These 6 cows are then taken out of the paddock to allow the grass to grow back.
After the grass has been allowed to grow back to the original amount, Freddie then puts 3 cows into the paddock. This time he finds that it takes 7 days for the 3 cows to eat all the grass in the paddock. Freddie is puzzled that the cows took this long and consults a mathematician.
Freddie said "Geez mate, I dunno why me cows took that long to eat me paddock."
Marvin the mathematician replies "Well Freddie, tell me what assumptions you made."
Freddie replies "Well mate, maybe me cows got sick or somethin', cos I reckon that me 3 cows should have taken 6 days to eat me paddock, not 7 days! "
Marvin Replies, "I doubt that very much Freddie!"
After a while Marvin does some calculations and reveals that Freddie had overlooked an important assumption.  What was the assumption Freddie had overlooked?  Using Marvin's assumption, how long would a single cow take to eat the same paddock?

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#334605 Crazy People

Posted by BMAD on 22 July 2013 - 01:44 PM


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#334529 Making something from nothing

Posted by BMAD on 20 July 2013 - 05:48 AM

using only five zeroes and mathematical operators make the number 25.

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#334430 Creative Paradox

Posted by BMAD on 18 July 2013 - 04:34 PM




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#334197 10-gon game

Posted by BMAD on 14 July 2013 - 03:18 PM

Spoiler for

remember right angled is not considered acute in the game's directions

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#333936 Creative Paradox

Posted by BMAD on 08 July 2013 - 04:13 AM

this is like my other post



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#333574 To-do Lists

Posted by BMAD on 28 June 2013 - 04:36 AM

who can conquer the world with aching calves?

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#332742 Crazy People

Posted by BMAD on 02 June 2013 - 04:35 AM


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#332741 Crazy People

Posted by BMAD on 02 June 2013 - 04:34 AM


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#332593 Find the common remainder.

Posted by BMAD on 27 May 2013 - 04:05 AM

480608 , 508811 , 723217. These three numbers, when divided by a certain natural number > 1 , all yield the same remainder. What is that divisor and that remainder?


The 'best answer' will be awarded to the person who can develop an elegant method that does not utilize brute force or code.

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#332586 Rolling a coin

Posted by BMAD on 27 May 2013 - 12:43 AM

We have two identical coins. And we roll the one on the left halfway around the other coin, so it rotates without slipping against the other coin, so that it ends up on the right of the other coin. It has rolled over a length of only half its circumference, and yet it has made one complete rotation. Which way is the head of the coin facing?

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#332585 A stand up Logician

Posted by BMAD on 27 May 2013 - 12:42 AM

Recently a self-proclaimed stand-up logician held a show with thirty people.  here is his opening dialogue:
Hello folks. It's an honor to be on Amateur Logician Night, here on the Internet. How many of you are from out-of-town? Let's see a show of hands.
Now, the people who raised their hands may be truth-tellers who are from out-of-town, or you may be liars who are from in-town. As the amateur logician, it is my job to determine who is really from out-of-town, and who is not. This is not an easy job, as you can well imagine.
If I were to ask how many of you are truth-tellers, then all of you would raise your hands. The liars would have to lie, and claim to be truth-tellers.
Now, let's see a show of hands, all of the people who raised your hands the first time, when I asked how many of you were from out-of-town. Very good. All of you, who now have your hands up, are from out-of-town.
Some of you are truth-tellers who raised your hands both times. You are from out-of-town. Some of you are liars who did not raise your hands last time. You too are from out-of-town. So, all of you who now have your hands up, are from out-of-town.
Thank you. Thank you. What a crowd. Thank you.



Would this approach work in identifying those that always lie and those that always tell the truth?  Why or why not?

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#332584 parallelogram conjecture?

Posted by BMAD on 27 May 2013 - 12:25 AM

Start with any general quadrilateral, and connect the midpoints of consecutive sides, making an inscribed quadrilateral as in the diagram. That inscribed quadrilateral, in the diagram, seems to be a parallelogram. Let me conjecture that this inscribed quadrilateral is a parallelogram with half the area of the original quadrilateral. Can you prove or disprove either part of my conjecture?


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#332583 Consecutive cubes and squares

Posted by BMAD on 27 May 2013 - 12:00 AM

Show that if the difference of the cubes of two consecutive integers is the square of an integer, then this integer is the sum of the squares of two consecutive integers.
(The smallest non-trivial example is: 83 − 73 = 169.  This is the square of an integer, namely 13, which can be expressed as 22 + 32.)


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