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## #1 2006-01-12 02:38:07

goggles1980
Member
Registered: 2006-01-12
Posts: 1

### Puzzle

Which number doesn't belong in this set?

73, 83, 86, 93

Obvious (ie. 86 because it's even) ? Or am I missing a deeper meaning of these numbers?

Another one, this one is for sure difficult.

What is depicted by the following:

8
u u u u
u u u

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## #2 2006-01-12 04:16:31

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

### Re: Puzzle

That's the problem with puzzles like that. You give a perfectly sensible answer, and then the designer of the puzzle says that the actual answer is something different and complex and feels really proud of themselves, even though they're actually just being childish.

e.g. What comes next in this sequence? A, A, A, A, A...?

Any sane person would answer A, but nooooo... the idiot who calls themselves a puzzle-maker says 'no yore rong cos its acshully the first leter of the continants lol'

Anyway, your answer is fine. It's probably not the intended one, but it's certainly the simplest.

The second puzzle is harder. I can't think of anything right now, but I'll keep pondering for a while.

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

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## #3 2006-01-12 09:35:54

MathsIsFun
Registered: 2005-01-21
Posts: 7,630

### Re: Puzzle

73 and 83 are primes, 86 and 93 are composite, so it isn't that.

And the other puzzle? Something to do with the eight being over 7 "u"s. They might look like "c" sideways? Seven Seas?

BTW: I like your continents one!

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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## #4 2006-01-12 13:20:17

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

### Re: Puzzle

Heres one:  what comes next in this sequence:

9, 10, 11, 12, 13, 14...

Once you've looked that, try to guess the pattern...

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

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## #5 2006-01-12 21:12:21

justlookingforthemoment
Moderator
Registered: 2005-05-26
Posts: 2,161

### Re: Puzzle

goggles1980 wrote:

8
u u u u
u u u

Maybe something to do with 'you underrate'?

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## #6 2006-01-14 17:36:20

ganesh
Moderator
Registered: 2005-06-28
Posts: 21,730

### Re: Puzzle

Sensible thinking. But why 7 'u's?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #7 2006-01-17 07:30:16

Zach
Member
Registered: 2005-03-23
Posts: 2,075

### Re: Puzzle

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.

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## #8 2006-01-17 10:18:18

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

### Re: Puzzle

But where do you get 'continents' from?

This is just an idea, but as they're c's on their side, it might be something do to with seaside.

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

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## #9 2012-12-08 12:32:25

mathaholic
Member
From: Earth
Registered: 2012-11-29
Posts: 3,247

### Re: Puzzle

I bet it's 86. Because the other 3 numbers end in 3.

Mathaholic | 10th most active poster | Maker of the 350,000th post | Person | rrr's classmate

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## #10 2012-12-14 21:22:18

mathaholic
Member
From: Earth
Registered: 2012-11-29
Posts: 3,247

### Re: Puzzle

Or it is 83 'cause it is prime.

Mathaholic | 10th most active poster | Maker of the 350,000th post | Person | rrr's classmate

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## #11 2012-12-14 22:50:59

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,018

### Re: Puzzle

Well, 73 is also prime...

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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