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  • 6 Post By Claire ex-ax
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Another maths problem

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  1. #1

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    Another maths problem

    It's for Vietnamese 8 year olds. All you need to do is place the digits from 1 to 9 in the the grid.



    Can you do the maths puzzle for Vietnamese eight-year-olds that has stumped parents and teachers? | Science | The Guardian


  2. #2

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    What is the ":" sign for? Should be easy to work your way back from the 66 number and reverse all the operators.


  3. #3

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    Quote Originally Posted by shri:
    What is the ":" sign for? Should be easy to work your way back from the 66 number and reverse all the operators.
    I guess it is a division sign?
    wtbhotia likes this.

  4. #4

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    Don't do it! Those kids will never learn anything if you do it for them!

    gunsnroses, greenmark, Mat and 3 others like this.

  5. #5

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    Quote Originally Posted by Claire ex-ax:
    Don't do it! Those kids will never learn anything if you do it for them!
    Ok, will pass it to the son and let him know that his birthday present depends on him solving it in 10 mins.

  6. #6

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    Quote Originally Posted by shri:
    Ok, will pass it to the son and let him know that his birthday present depends on him solving it in 10 mins.
    You're a cruel man, shri. Give him 15 minutes.

  7. #7

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    The ":" represents a ratio which means division. Also, the question does not say you have to use all the digits between 1 and 9, so you can repeat, which makes it easier. But the only way to solve for it is trial and error.

    A+13xB/C+D+12xE-F-11+GxH/I-10 = 66 which simplifies down to A + (13B/C) + D + 12E - F + (GH/I) = 87 since order of operators matter. One can also assume B/C and GH/I must be integers and not fractions to keep it simpler.

    shri likes this.

  8. #8

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    If you can repeat numbers then I think it is age appropriate. If you can only use each number once then there is a little bit of strategy involved. But obviously there is more than one answer (since A and D are interchangeable as are G and H).


  9. #9

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    Using Excel and a little bit of trial and error - 531726984 is one solution.