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Guest Message by DevFuse
 

BMAD

Member Since 18 Feb 2013
Offline Last Active Dec 20 2014 04:56 AM
*****

#331880 Set Theory

Posted by BMAD on 09 May 2013 - 09:44 PM

Let A be a list of n integers between 1 and k. Let B be a list of k integers between 1 and n. Prove that there's a non-empty subset of A and a (non-empty) subset of B having the same sum.

 

 

Example: Say n=3, k=5 and A={3,4,5}, B={1,1,2,3,3}. Then we can find {1,3,3} is contained in B and {3,4} contained in A with the same sum (I know there're are simpler solutions in this example, it's just for demonstration).

 


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#331275 Creative Paradox

Posted by BMAD on 26 April 2013 - 01:56 AM

Not sure of the title of this paradox so I didn't know how to search the forums

 

 

creative-Paradox-drawing-impossible.jpg


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#330878 The Adventure

Posted by BMAD on 19 April 2013 - 01:06 AM

I would pee a line separating between me and the cougar(s)


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#330807 Particle detectors

Posted by BMAD on 18 April 2013 - 03:44 AM

Spoiler for

Spoiler for

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#330534 Crazy People

Posted by BMAD on 11 April 2013 - 03:11 AM

.

Attached Images

  • find_x.jpg

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#330451 Powers separated by 5

Posted by BMAD on 08 April 2013 - 11:23 PM

Find pairs of positive integers where 2a = 3b + 5.  Prove that you have found them all.


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#330375 Crazy People

Posted by BMAD on 05 April 2013 - 07:02 PM

  1. The next sentence is true but you must not believe it
  2. The previous sentence was false

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#330363 Crazy People

Posted by BMAD on 05 April 2013 - 04:29 PM

Proof : 1 Clever Person = 1 mad person

assume 1 clever person

           = 1/2 clever person + 1/2 clever persons

( if one person is 1/2 clever that means he is 1/2 mad )

          = 1/2 mad + 1/2 mad

         =  1 mad.

hence proved.
 


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#330362 Crazy People

Posted by BMAD on 05 April 2013 - 04:28 PM

eq ( 1 ) Study =  not failed

eq. ( 2 ) not study = failed

add eq ( 1 ) & ( 2 )

study + not study = fail + not fail

study ( 1 + not ) = fail ( 1 + not )

study = fail

Then why should we study??
 


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#330341 Crazy People

Posted by BMAD on 05 April 2013 - 02:56 AM

Theorem: All numbers are boring.
Proof (by contradiction):
        Suppose x is the first non-boring number.  Who cares?
 


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#330338 Crazy People

Posted by BMAD on 05 April 2013 - 01:54 AM


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#330337 Crazy People

Posted by BMAD on 05 April 2013 - 01:52 AM


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#330335 Crazy People

Posted by BMAD on 05 April 2013 - 01:45 AM

$1 = 100 cents
= (10 cents)2
= ($0.1)2
= $0.01
= 1c


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#329583 clever Timmy

Posted by BMAD on 12 March 2013 - 05:37 PM

Answers

Spoiler for

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#329234 Crazy People

Posted by BMAD on 02 March 2013 - 11:51 PM

A biologist, a physicist and a mathematician were sitting in a street cafe watching the crowd. Across the street they saw a man and a woman entering a building. Ten minutes they reappeared together with a third person.
- They have multiplied, said the biologist.
- Oh no, an error in measurement, the physicist sighed.
- If exactly one person enters the building now, it will be empty again, the mathematician concluded. 


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