Half of Five
Logic puzzles require you to think. You will have to be logical in your reasoning.
If half of 5 is 3; then how much is
onethird of 10?
Answer
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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Comments
dewtell
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? 
fishmed
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. 
canu
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
onethird of 10 is 37054872" or "If half of 5 is 3; then onethird 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!! 
sdm1177
Jul 10, 2005
 Or if you "round up", then 10 / 3 = 3.333, rounded up is 4. 
Crazycriely
May 12, 2006
 this is pretty lame. since when is 5=6? 
ava199345
Aug 22, 2006
 i just guessed and i got it right 
foraneagle2
Nov 15, 2006
 i second the illogic category idea 
scallio
Mar 13, 2007
 That was a complicated way to say you round up to the nearest whole number. 
Subtox
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. 
hersheyugget
Apr 28, 2007
 wth? 
leftclick
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. :? 
Starriddler
Oct 05, 2008
 Everyone else is right.
This could be translated like this:
IfThe
Half ofanswer
5to this
isis
3,french
thenfries
onethird of 10.
is.
what?. 
javaguru
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? 
javaguru
Feb 11, 2009
 I meant "47 is really two" above...I got confused about what my imaginary number system was. 
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