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Ok here's another one for you brainiacs...

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  #1  
Old 10-24-2002
Newcomer, in training
 
Location: Honolulu, HI
Member since: Feb 2002, 10 posts
Ok here's another one for you brainiacs...

Three men check in at a motel. The rate is $30 so they split it evenly $10 ea. Later, the manager remembers the rate is only $25 so he sends a bellboy up to their room with the difference. However, the bellboy realizes he can't evenly split the $5 three ways so he keeps $2 and gives the men back $1 each. So $9x3=$27+$2(bellboy)=$29...where did the other $1 go!?
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  #2  
Old 10-24-2002
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Is this the best you can do????

You are adding up the wrong numbers. You are assuming that these numbers must be added to reach 30 when in fact they should equal 25 with a subtraction. They payed nine dollars each with the refund, and they never knew that other two dollars were refunded, so you have 27 dollars paid plus a 3 dollar refund = $30. The other two bucks are insignificant, and not necessary to add to the total. The two bucks bit is just put in to throw you off the scent and detract from the logical certainty that a whole single digit 1 cannot disappear magically from a sum. That's impossible.

30-5=25 25+2(bellboy)=27 27+3(refund)=30
9*3=27 27+3=30.......easy
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  #3  
Old 10-24-2002
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Ahhh... after 10 minutes of brainstorming I couldn't get a clear solution, I knew something was missing, but anyway, I was so mad about it I just had to Google it

I was about to post the answer here as a reply but then I thought it would be much more fun if you guys can have a clear attempt on solving the problem, if you get too frustrated, here you are: MathForum.

Nice post, too kainoa, welcome aboard and keep em coming.
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  #4  
Old 10-24-2002
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Quote:
Originally posted by Phantasm66
Is this the best you can do????
Heh, you either knew the problem from somewhere else or are too smart for me... maybe I could have spent some more time trying to solve it but I get kinda frustrated too fast
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  #5  
Old 10-24-2002
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Here's where I come clean and say that I have worked out this problem before a while ago. The trick is more in the wording than anything else as when you follow the calculation at the end you see that its totally nonsense and not a representation of what happened.
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  #6  
Old 10-24-2002
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OK, here is a pretty easy one:

What comes NEXT in this sequence:

1,2,3,5,8,13,??



...Oh, and WHY???

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  #7  
Old 10-24-2002
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Quote:
Originally posted by Phantasm66
OK, here is a pretty easy one:

What comes NEXT in this sequence:

1,2,3,5,8,13,??
Each following number is the last two numbers added together...
Like you said - Easy...

But i still can't get my head around that first one
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  #8  
Old 10-24-2002
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Quote:
Originally posted by RustyZip
Each following number is the last two numbers added together...
Like you said - Easy...

But i still can't get my head around that first one

So the next number IS????

21.

The first one is not as hard as it looks. Try to ignore the calculation bit here:

So $9x3=$27+$2(bellboy)=$29...where did the other $1 go!?

Which is basically crap and not what happened. Don't look at that bit of the riddle, its put in to confuse you.
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  #9  
Old 10-24-2002
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Go to that link I posted before, good explanation with the table and all that, but like P66 said once you look at it clearly, it's not much of a math trick (the way I was trying to look at it) but rather a wording thing, a very tricky wording thing
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  #10  
Old 10-24-2002
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The reason the first one looks messed up is because the $25 rate couldn't be split into 3 evenly. 24 is the nearest integer divisible by 3. Each man should actually be paying out $8.33 1/3

LNCPapa
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  #11  
Old 10-24-2002
Phantasm66's Avatar
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Quote:
Originally posted by LNCPapa
The reason the first one looks messed up is because the $25 rate couldn't be split into 3 evenly. 24 is the nearest integer divisible by 3. Each man should actually be paying out $8.33 1/3

LNCPapa
I thought that originally too, but the answer isn't in thinking in terms of split dollars....

Try forgetting that the bellboy is in the question and that the whole bill is $27 instead of $25. That bit is stuck in to confuse you. They each got $1 back. 3 x $1 = $3 plus $27 = $30.

The sum at the end is WRONG but its set up in a way that looks right but isn't. That sum does not express what happened in this transaction.

Instead of reading the question the way its phrased, try thinking about what actually happened. The question is phrased in a way that's deliberately confusing, and then the sum at the end is pretty much a load of crap. Its not adding the correct numbers together, and so its producing a wrong total.



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  #12  
Old 10-24-2002
Newcomer, in training
 
Location: Honolulu, HI
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Nice try guys. Took me a while to figure this one out myself. How long did it take you 66 (when you tried it the FIRST time)?

As for the still confused the clearest explaination I can give is that when the bellboy takes the $2, the total amount the men pay for the room actually becomes $28 or $9.33ea (NOT $27 as does the riddle falsely imply).

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  #13  
Old 10-24-2002
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I knew that the answer obviously wasn't right so I drew out on a piece of paper what was happening and realised that it was very simple. Probably about 5 mins or so....
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  #14  
Old 10-24-2002
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Location: Honolulu, HI
Member since: Feb 2002, 10 posts
HEHE...i drew it out too but i still couldnt see it!
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  #15  
Old 10-24-2002
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Location: Southern California
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Ok, heres a nice one for you

For a closed set of numbers,{1-20}

8, 18, 11, 15, X, 4, 14, X, 19, X, 7, 17, 6, X, 10, 13, 3, X, X, 2



Place the following numbers into the proper order within the sequense.


1, 5, 9, 12, 16, 20



You'll have to think "outside the box" on this one.
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  #16  
Old 10-24-2002
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Location: Jefferson City, MO, USA
Member since: Oct 2002, 700 posts
Easy:

8, 18, 11, 15, 5, 4, 14, 9, 19, 1, 7, 17, 6, 16, 10, 13, 3, 12, 20, 2


Not quite outside of the box. Maybe written on it though.
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  #17  
Old 10-25-2002
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Yeah writing it down helps a lot
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  #18  
Old 10-25-2002
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Think about what REALLY happened and you will realise that its simple.... 30 minus 27 is 3....
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  #19  
Old 08-09-2003
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Quote:
Originally posted by Phantasm66
OK, here is a pretty easy one:

What comes NEXT in this sequence:

1,2,3,5,8,13,??



...Oh, and WHY???
'


13 + 8 is 21...

21 + 13 is 34...


fibernaci(?)s golden ratio
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  #20  
Old 08-09-2003
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Thought RustyZip already covered that one soul
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