Math Is Fun Forum

siva.eas

Member

Registered: 2005-09-17

Posts: 166

A very interesting problem

Here is a problem for the world's best and the brightest to ponder about? Can anyone answer the following questions.

10) Which of the sentences below cannot be wrong? Explain.   
a) The Earth orbits the Sun.   
b) Cats cannot lay eggs.   
c) You cannot be me.   
d) If João is Pedro’s son, João was born after Pedro.   
e) The choices ‘a’ and ‘b’ are correct.   
f) The choices ‘a’ and ‘c’ are correct.   
g) The choices ‘a’ and ‘d’ are correct.   
h) The choices ‘b’ and ‘c’ are correct.   
i) The choices ‘b’ and ‘d’ are correct.   
j) The choices ‘c’ and ‘d’ are correct.   
k) The choices ‘a’, ‘b’ and ‘c’ are correct.   
l) The choices ‘a’, ‘b’ and ‘d’ are correct.   
m) The choices ‘a’, ‘c’ and ‘d’ are correct.   
n) The choices ‘b’, ‘c’ and ‘d’ are correct.   
o) All the above are correct.   
p) None of the above is correct.

Zach

Member

Registered: 2005-03-23

Posts: 2,075

Re: A very interesting problem

My first answer would be O; as if all the above are correct e) through to n) would be correct, the Earth does orbit the sun, Cats are mammals and give birth to living young, you being me would be illogical and João is Pedro’s son.

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Boy let me tell you what:
I bet you didn't know it, but I'm a fiddle player too.
And if you'd care to take a dare, I'll make a bet with you.

mathsyperson

Moderator

Registered: 2005-06-22

Posts: 4,900

Re: A very interesting problem

Zach's right, unless you're a philosopher who refuses to believe anything.

For a), Einstein's relativity thing says that it might be the sun moving around the earth and we wouldn't know the difference.

For b), I can't think of anything good. It's a long shot, but I suppose you could say that a cat might pick up an egg and then lay it down somewhere.

d) is possible through adoption, although it would certainly be strange.

[...And I would have proved c) possible by posting as a guest, but that's been disabled now.]

Last edited by mathsyperson (2005-12-26 23:10:08)

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Why did the vector cross the road?
It wanted to be normal.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,384

Re: A very interesting problem

I concur with Zach's and mathsyperson's views, although I find mathsy's counterexamples quite funny!

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

jU

Real Member

Registered: 2005-08-17

Posts: 1,923

Re: A very interesting problem

so do I

VR Hawks

Member

Registered: 2005-11-26

Posts: 401

Re: A very interesting problem

Correct.

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Name :: Vincent Raider Hawks
Gender :: Male
Birth Date :: July 4 , 1970