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Guest Message by DevFuse
 

bonanova

Member Since --
Offline Last Active Yesterday, 08:30 PM
*****

#331239 Particle detectors

Posted by bonanova on 25 April 2013 - 03:11 AM

ok, why is a circular detector bigger than the square detector ?

 

Circles aren't bigger or smaller than squares until constraints are added.

  1. If the constraint is a given perimeter, circles are bigger (area wise)
  2. If the constraint is maximum and minimum values of x and y, then squares are bigger.

The present constraints are of the second type.


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#330671 Particle detectors

Posted by bonanova on 16 April 2013 - 07:37 AM

Spoiler for Clarification


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#330616 Alhazen's problem expanded

Posted by bonanova on 14 April 2013 - 07:14 AM

Spoiler for The basic problem


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#330463 Powers separated by 5

Posted by bonanova on 09 April 2013 - 11:23 AM

Spoiler for for starters


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#330425 Balancer's Chess

Posted by bonanova on 07 April 2013 - 07:03 PM

What if there were no diagonals?

 

Spoiler for And no empty quadrants

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#329908 Four darts

Posted by bonanova on 23 March 2013 - 12:21 AM

The puzzle may have run its course. Probability is ratio of areas, and the triangle area is an hellacious multiple integral. The problem is known as Sylvester's four point problem.

I did find the number, as RG gave it, from simulation, not calculation. Uniform point-picking, necessary to form uniformly distributed triangles was an issue. Equally likely radius and angle gives preference to central points.

What was interesting to me when I simulated was that I was off by a factor of four that the four points would not be convex. That is, and should be 4 time the probability the 4th dart lands inside the triangle. There are three other areas the 4th dart can land that make a non-convex configuration, and those areas, on average, are equal to the triangle size. Not an intuitive result until you realize any of the darts can be taken to be the 4th dart.

So my last question now does not need to be asked, namely, to compare the probabilities of the two cases in the OP. also, that question has been answered in this thread.

Also, the mean triangle area was (to me) surprisingly small.
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#329821 Number game 1

Posted by bonanova on 19 March 2013 - 10:44 AM

 

1 2 3 4 5 6 7 8 9

Arrange these numbers into two separate groups so that they add up to same total.

Note : you cant turn 9 upside down and make it 6

 

Spoiler for Looks like

this is what even i think how can you split 45 into two equal parts...P.S- he noted that we cant use 9 as 6... :blink:

 

Ah, I misread that. Good catch. :duh:

 

Spoiler for but


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#329652 Complete the Series 2

Posted by bonanova on 14 March 2013 - 04:31 PM

Spoiler for

 

:duh:  Good solve ...  although I got the "basic" nature of the puzzle, I did not see the second "?" in the OP.


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#329547 How many tickets?

Posted by bonanova on 12 March 2013 - 12:39 AM

 



Suppose n tickets numbered 1-n are in a box, and you draw one of them
You don't know how many tickets are in the box, but you are asked to estimate how many there are.
Your ticket has the number p on it.
 
What estimate of n has the highest likelihood of being correct?

 
It seems like this problem is dependent upon what is a reasonable a priori distribution for N.
Spoiler for
 
 
Oh wait, the answer is much simpler than that. Turns out this is the easiest bonanova puzzle I have ever seen =)
Spoiler for

LOL

That may be the first and only time I use LOL in this forum.

 

I'm not that clever. Really.

But I love it. It's a better puzzle than the one I intended.

Honorable mention.

.


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#329440 Give a monkey enough rope

Posted by bonanova on 09 March 2013 - 02:32 AM

Spoiler for is Russian translation available?

 Конечно ...  ^_^ Веревка подбежал шкив, на одном конце была обезьяна, на другом конце вес.Два оставшихся в равновесии.Вес каната было 4 унции / футбол, а в возрасте от обезьяны и мать обезьяны составил четыре года.Вес обезьяна была много фунтов, как мать обезьяны было лет, и весом весом и весом каната вместе были в полтора раза больше, поскольку вес обезьян.
 
Вес вес превышал вес веревки, как многие фунтов, как обезьяна лет, когда мать обезьяны был вдвое старше брата обезьяны было, когда мать обезьяны был вдвое старше брата обезьяна будет, когда брат обезьяны в три раза стара, как мать обезьяны Когда мама была обезьяна была в три раза стара, как обезьяна в пункте 1.
 
Мать обезьяны был вдвое старше обезьяна Когда мать обезьяны был наполовину стара, как обезьяна будет Когда обезьяна в три раза стара, как мать обезьяны было, когда мать обезьяны в три раза стара, как обезьяна в пункте 1.
 
Возраст матери обезьяны превысил возраст брата обезьяны на такую ​​же сумму, как возраст брата обезьяны превысил возраст обезьяны.
 
Какова была длина веревки?
  :lol:  :lol:  :lol: So the rope has legs and plays footbal?! And monkey's mother is a male?! And age is money?!Was it Google translation? I guess, it'll be awhile before computers can understand and translate natural language.Although it's worth noting that about the only bit translated correctly, is that very thing, which I misunderstood. The translation states, the weight of the rope together with the weight is 1.5 times the weight of the monkey, as the problem statement intended. Whereas I understood it as half weight of the monkey.

I was going to add the caveat that I cannot verify the usefulness of google translate. But yes, I thought all monkeys played football. ;)
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#329405 4 x 4 cards

Posted by bonanova on 08 March 2013 - 09:59 AM

Spoiler for what about this

IN SECOND ROW  SECOND COLUMN IT SHOULD BE 'KH'. I TRIED TO EDIT THE POST BUT EDITING FAILED.

 

Hint: To edit after time elapses, copy / edit / paste onto a new post. ;)


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#329101 Give a monkey enough rope

Posted by bonanova on 26 February 2013 - 10:10 AM

This has languished for a couple of weeks ...
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#328901 Stopping and Turning back hands of time

Posted by bonanova on 21 February 2013 - 11:36 PM

Here's what I think.

Spoiler for Analysis


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#328360 Give a monkey enough rope

Posted by bonanova on 16 February 2013 - 05:48 AM

I am giving this puzzle verbatim from a book I read long ago. These days most everything I have ever done was long ago. But I digress. I simply don't trust myself to re-cast it into scintillating banter style. So if its tenor is archaic or arcane, the onus is off me.  Enjoy.
 
A rope ran over a pulley; at one end was a monkey, at the other end a weight. The two remained in equilibrium. The weight of the rope was 4 oz/foot, and the ages of the monkey and the monkey's mother amounted to four years. The weight of the monkey was as many pounds as the monkey's mother was years old, and the weight of the weight and the weight of the rope were together half as much again as the weight of the monkey.
 
The weight of the weight exceeded the weight of the rope by as many pounds as the monkey was years old when the monkey's mother was twice as old as the monkey's brother was when the monkey's mother was twice half as old as the monkey's brother will be when the monkey's brother is three times as old as the monkey's mother was when the monkey's mother was three times as old as the monkey was in paragraph 1.
 
The monkey's mother was twice as old as the monkey was when the monkey's mother was half as old as the monkey will be when the monkey is three times as old as the monkey's mother was when the monkey's mother was three times as old as the monkey was in paragraph 1.
 
The age of the monkey's mother exceeded the age of the monkey's brother by the same amount as the age of the monkey's brother exceeded the age of the monkey.
 
What was the length of the rope?


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#328354 Why isn't this a legitimate answer?

Posted by bonanova on 16 February 2013 - 03:48 AM

Interesting post.
 
In theology Wesley defined "sin" as "willful transgression of a known law of God."
So, an act could be a sin or not, based on the actor's state of knowledge or intent.
 
Many logicians attribute the prefix "It is true that ..." or "It is the case that ..." to all declarative statements.
That permits a paradox to become instead a simple contradiction.
 
In American courts, there is a permissible disclaimer of "upon information and belief" that allows a witness to tell things as s/he knows them without saddling them with proving the truth of their statements.
 
If we take the liar's paradox as [possibly flawed] informal conversation, we get some added "outs" from the paradox.
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