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RedRose · Joined: 21 May 2004 Posts: 2735 Location: GuangZhou, China

UKbug, you can give us more brian stormings

UKbug · Joined: 18 Aug 2006 Posts: 113

SURE!! i WILL!!!!!

hoshi · Posted: Sat Mar 31, 2007 7:44 am Post subject:

UKbug · Joined: 18 Aug 2006 Posts: 113

then that's cool!!! did u ask he or she about it???

Anuradha Chepur · Joined: 20 May 2006 Posts: 933

A man is driving to London, but he is not sure if the road he has taken is the right one.
He meets two people A and B on the way.
One of the two always speaks the truth and the other one always speaks lies. But we don't know which one of them is the liar and which one is truthful.
The man has to talk to one of them and find out if the road goes to London.

The rules:
1. He is allowed to talk to only one of them, i.e., either A or B.
2. He is allowed to ask only one question.

So who of the two will the man talk to and what question will he ask, so that the answer he would get would tell him whether the road goes to London or not.

beancurdturtle · Posted: Mon Apr 02, 2007 1:38 am Post subject:

Oh!

This is like playing chess.

My poor little weak brain hurts.

Sad

_________________
Daniel

�Be who you are and say what you feel because those who mind don't matter and those who matter don't mind.�
--Dr. Seuss

hoshi · Posted: Mon Apr 02, 2007 10:31 am Post subject:

ad-miral · Joined: 01 Sep 2006 Posts: 1488

I have a suggestion. But I can't have more possible ways than 2 and I have to be sure that one of two ways is the correct one.

I would ask one of them: "Which way would your fellow suggest if he had been asked for the right way?"

The liar would say the wrong way because his fellow (the truthteller) always says the right way. And the truthteller would also say the wrong way because he knows that the other one lies and he would also say the wrong way.

Mr. Green

oh my head
_________________
If I say "I love you" to someone, then I also have to say "I also love everyone else inside you, I love the whole world because of you, I also love myself inside you." -- Erich Fromm, the Art of Love

hoshi · Posted: Mon Apr 02, 2007 2:06 pm Post subject:

Hey I saw a game in another forum
Here are the rules:
A first person starts giving us a "brain storming" (Like Linda's one) then all the people try to get the answer (guess) until a really jolt person says the correct answer. Then the person who got the right answer has to make another "brain storming" for us and it continues and continues... we have fun and a terrible funny headache Cool

The game is started now... we only have to continue playing Wink

_________________
God gave us two ears to hear, two eyes to see and two hands to hold. But why did God gave us only one heart? Because He wants us to find the other one!

Anuradha Chepur · Joined: 20 May 2006 Posts: 933

Admiral has the answer!!!
Only thing is he hasn't expressed it that clearly.

He may talk to either of them and follow the opposite of the answer he would get. For instance if he is talking to A, he will ask:

If I ask B whether this road leads to London, what would he say?

If the road does lead to London, then B would say Yes if he speaks the truth and say No if he is a liar. But when A is asked the above question, A will say No if he is a liar and also say No if he is
speaking the truth.

The opposite of No is Yes, so the road does lead to London.

If the road does not lead to London, then B would say No if he speaks the truth and say Yes if he is a liar. But when A is asked the above question, A will say Yes if he is a liar and also say Yes if he is speaking the truth.

The opposite of Yes is No, so the road does not lead to London.

The same logic would apply if the man were to ask the question to B about A.

Congratulations Admiral. Very Happy

beancurdturtle · Posted: Wed Apr 04, 2007 12:48 am Post subject:

Oh! My poor witless head hurts.
_________________
Daniel

�Be who you are and say what you feel because those who mind don't matter and those who matter don't mind.�
--Dr. Seuss

Anuradha Chepur · Joined: 20 May 2006 Posts: 933

beancurdturtle · Posted: Wed Apr 04, 2007 7:41 am Post subject:

Ok then...

Lets say you have six spheres all the same shape. Two spheres are silver colored, two are gold colored, and two are copper colored.

One sphere in each of the pairs is lighter. The three lighter spheres are the same weight as each other, the three heavier spheres are the same weight as each other.

You also have a balance scale. In just two weighings, find which three spheres are light, and which three are heavy.
_________________
Daniel

�Be who you are and say what you feel because those who mind don't matter and those who matter don't mind.�
--Dr. Seuss

ad-miral · Joined: 01 Sep 2006 Posts: 1488

Well, I would take a testtube full of water. (Better would be such a thing which stands):

And it should have measures like

(the size of the testtube is dependent on the size of the spheres/ balls. My solution is only for balls which fit into the testtube)

so you throw the balls into the testtube full of water, a silver one, a gold one, and a copper one, and then you measure the amount of displaced water. (Or if you are not allowed to measure then you just take 3 testtubes and you compare)
As the lighter ones have the same weight and the heavy ones have the same weight, you can easily match them.

Testtubes are in every school or university, in the chemistry or physics room.

(I doubt this is the right answer so I don't post another puzzle)
_________________
If I say "I love you" to someone, then I also have to say "I also love everyone else inside you, I love the whole world because of you, I also love myself inside you." -- Erich Fromm, the Art of Love

beancurdturtle · Posted: Sat Apr 07, 2007 9:27 am Post subject:

you have to use a balance scale.

_________________
Daniel

�Be who you are and say what you feel because those who mind don't matter and those who matter don't mind.�
--Dr. Seuss