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More ways to get Braingle...

1 2 3 4 5 6 7 8 9 = 100

Math brain teasers require computations to solve.

 

Puzzle ID:#376
Fun:*** (2.67)
Difficulty:*** (2.17)
Category:Math
Submitted By:Mr. GAus*****
Corrected By:CinnamonBaby123

 

 

 



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

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Comments

Shorty12
Feb 03, 2005

FUN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Sane**
Mar 16, 2005

That was actually pretty tricky.
dutchymonster*en*
Sep 02, 2005

the hint made it a lot easier, but still pretty tricky. fun though
Shawnheyhey123Aus*
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+5x6-7+8+9=100
horse_luverAca*
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!
thompson1Aus*
Mar 14, 2006

Actually, Shawn, you couldn't do that because it says you can only use 3 symbols.
jj_is_coolAus*
Mar 29, 2006

shawn is my brother, i wish
Vigo95Aus*
Mar 29, 2006

why are you trying so hard to make me think ?!!
i will not do it !!!
calmsaviorAus*
May 03, 2006

Shawneyheyhey123 is wrong.

you can only use three symbols!
flowerz2010Apk*
Aug 24, 2006

got it with the hint
slicktrumpetAus*
Apr 10, 2007

Very clever!
javaguru*us*
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 4-digit, or a 4-digit and 3-digit number, or two 3-digit numbers that were close, so it had to be one 3-digit number and three 2-digit numbers. The 3-digit 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.

Piece-o-cake!




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