1 2 3 4 5 6 7 8 9 = 100
Math brain teasers require computations to solve.
Can you place + and  signs between the following numerals to make the equation true? You can only use a total of 3 symbols and you cannot rearrange the numerals.
1 2 3 4 5 6 7 8 9 = 100
HintYou will use   +, in that order.
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Answer
123  45  67 + 89 = 100
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Comments
Shorty12
Feb 03, 2005
 FUN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
Sane
Mar 16, 2005
 That was actually pretty tricky. 
dutchymonster
Sep 02, 2005
 the hint made it a lot easier, but still pretty tricky. fun though 
Shawnheyhey123
Dec 09, 2005
 I had a different way of doing it. I thought it was a trick and you could change the + to an x by turning it on it's side and do:
1+2+3+4+5x67+8+9=100

horse_luver
Jan 22, 2006
 I recently had a challenge in this regard... come up with as many solutions as possible, except you can use x , / and brackets as well. I got 21. Anyway, this teaser is a really interesting variation! fun! 
thompson1
Mar 14, 2006
 Actually, Shawn, you couldn't do that because it says you can only use 3 symbols. 
jj_is_cool
Mar 29, 2006
 shawn is my brother, i wish 
Vigo95
Mar 29, 2006
 why are you trying so hard to make me think ?!!
i will not do it !!! 
calmsavior
May 03, 2006
 Shawneyheyhey123 is wrong.
you can only use three symbols! 
flowerz2010
Aug 24, 2006
 got it with the hint 
slicktrumpet
Apr 10, 2007
 Very clever! 
javaguru
Jan 16, 2009
 Got it in less than thirty seconds without the hint.
Since only three symbols could be use either two, three or four of the numbers needed to be relatively close in value. There wasn't any way to make two 4digit, or a 4digit and 3digit number, or two 3digit numbers that were close, so it had to be one 3digit number and three 2digit numbers. The 3digit number had to be 123, which left 45, 67 & 89. The 23 from 123 had to go with 89, so 45 and 67 had to be the negatives and 123 and 89 the positives. No trial and error, just wrote out the solution.
Pieceocake!

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