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## #1 2006-02-12 03:59:49

espeon
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### Einstein's problem: how many solutions can you find?

Einstein wrote this when he was 6 yrs old.

1+2+3-4+5+6+78+9=100

Keeping the digits1-9 in acsending order and only using + and - signs can you make 100? How many solutions can you find?

(You are allowed to stick numbers together to make bigger numbers like 7+8=78)

Presenting the Prinny dance.
Take this dood! Huh doood!!! HUH DOOOOD!?!? DOOD HUH!!!!!! DOOOOOOOOOOOOOOOOOOOOOOOOOD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

## #2 2006-02-15 23:59:09

Yutz
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### Re: Einstein's problem: how many solutions can you find?

123+45-67+8-9=100

Got One!!!

## #3 2006-02-16 00:35:25

Yutz
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### Re: Einstein's problem: how many solutions can you find?

123-4-5-6-7+8-9=100

Yutz is the man!

## #4 2006-02-16 01:21:10

espeon
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### Re: Einstein's problem: how many solutions can you find?

Double well done!

Presenting the Prinny dance.
Take this dood! Huh doood!!! HUH DOOOOD!?!? DOOD HUH!!!!!! DOOOOOOOOOOOOOOOOOOOOOOOOOD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

## #5 2006-02-16 01:36:56

Yutz
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### Re: Einstein's problem: how many solutions can you find?

1+23-4+56+7+8+9=100

Got another...im awesome!

## #6 2006-02-16 01:44:27

espeon
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### Re: Einstein's problem: how many solutions can you find?

Wow you've done it again... You ARE good!

Presenting the Prinny dance.
Take this dood! Huh doood!!! HUH DOOOOD!?!? DOOD HUH!!!!!! DOOOOOOOOOOOOOOOOOOOOOOOOOD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

## #7 2006-09-01 06:06:40

Devantè
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### Re: Einstein's problem: how many solutions can you find?

1+(23*4)+5-6+7-8+9=100
1+2+3+4+5+6+7+(8*9) = 100

This is fun.

I'll come up with more when I get the time.

EDIT: Popped in my head.

123-4-5-6-7+8-9=100

Last edited by Devanté (2006-09-01 06:07:16)

## #8 2006-09-01 06:11:13

Devantè
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### Re: Einstein's problem: how many solutions can you find?

Oops, forget the first two, just noticed that no multiplication is allowed.

## #9 2006-09-01 07:53:09

mathsyperson
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### Re: Einstein's problem: how many solutions can you find?

And your other one's been said already. Bad luck.

12+3+4+5-6-7+89=100
12-3-4+5-6+7+89=100
12+3-4+5+67+8+9=100
1+2+34-5+67-8+9=100
123+4-5+67-89=100

5 points to me.

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

Zhylliolom
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## #11 2006-09-01 12:34:02

Ricky
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### Re: Einstein's problem: how many solutions can you find?

Can you define the variables?  Integers?

"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..."

## #12 2006-09-01 16:38:22

Devantè
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### Re: Einstein's problem: how many solutions can you find?

#### mathsyperson wrote:

And your other one's been said already. Bad luck.

Argh...

I have seen some different versions of the problem, though. One where they don't have to be in consecutive order, one that can have no addition or subtraction, one with only exponents, etc.

So I'm assuming that this thread's version is the real one?

EDIT: http://www.physicsforums.com/showthread.php?t=96467

This isn't always a reliable source, so don't believe everything they say about the rule.

Last edited by Devanté (2006-09-01 16:40:59)

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