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Half of Five

Logic puzzles require you to think. You will have to be logical in your reasoning.


Puzzle ID:#651
Fun:** (2.02)
Difficulty:** (2.01)
Submitted By:vikass***
Corrected By:boodler




If half of 5 is 3; then how much is
one-third of 10?


Answer: 4
If half of five is 3, then 5 is not actually
five; it represents 6. If 5 represents six,
then 10 would in fact represent 12.


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Aug 09, 2002

I don't like the explaination in the answer.
My answer was 3: the answers are rounded to the nearest
integer, with the usual convention that .5 gets rounded up.
Or it could be 4, if the answers are simply rounded up.
But I don't follow the reasoning that "if 5 is really 6, then 10 must be 12."
If 5 isn't really 5, then why should we assume that one third is the
same as division by three?
Aug 12, 2003

And John Lennon is the Walrus. These puzzles that make you suspend regular rules are more difficult as you can't really figure any reliable pattern, like you said about 1/3 really being division by 3. If half of 5 equals 3, then 3 is really 2.5 and then 1/3 of 10 is really 1/2.5 of 10, being 4, so go figure.
Jul 14, 2004

There's a rule in reasoning: -----
If the antecedent is false, the reasoning is true regardless of the consequent.
So: "If half of 5 is 3; then
one-third of 10 is 37054872" or "If half of 5 is 3; then one-third of 10 is 0" are both true.
This teaser belongs in the Logic section, or perhaps in a new Illogic section.
(user deleted)
May 11, 2005

I'd love to see that section!!
Jul 10, 2005

Or if you "round up", then 10 / 3 = 3.333, rounded up is 4.
May 12, 2006

this is pretty lame. since when is 5=6?
Aug 22, 2006

i just guessed and i got it right
Nov 15, 2006

i second the illogic category idea
Mar 13, 2007

That was a complicated way to say you round up to the nearest whole number.
Mar 22, 2007

The number '5' is just being used as a variable to represent 6, and '10' is a variable that represents a number twice its size. So it is saying, "if x / 2 = 3, then 2x / 3 = ?" I understand the reasoning, but I only got it right because I thought the numbers were simply being rounded up.
Apr 28, 2007

Aug 05, 2007

The answer says that "half of 5 is 3" implies that "5" is a variable to represent "6". But it could equally imply that "half of" is a variable meaning "one million times" or that "3" is a variable meaning "pi"...

The answer could be anything. :?
Oct 05, 2008

Everyone else is right.
This could be translated like this:
Half of-answer
5-to this
one-third of 10-.
Feb 11, 2009

I had the same answer as dewtell: three or four. Assuming you are taking half of something that can't be divided (such as half the children), then the meaning of half is "half rounded" or "half truncated".

This answer doesn't require the creation of new rules of math and number values, and I think has to be considered the correct answer. Otherwise I could say that the answer is 47 because five is really 22 and three is really 11 and 10 is really six and 47 is really three.

Who approves these?
Feb 11, 2009

I meant "47 is really two" above...I got confused about what my imaginary number system was.

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