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Math Help - i really need help, its not that hard

  1. #1
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    i really need help, its not that hard

    wich one does not belonq??? and why???


    72 27 342 343
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  2. #2
    Grand Panjandrum
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    Quote Originally Posted by Heidi View Post
    wich one does not belonq??? and why???


    72 27 342 343
    They are all divisible by 3 and 9 except for 343.

    or: the digit sums are all 9 except for 343.

    RonL
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  3. #3
    Senior Member nikhil's Avatar
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    Quote Originally Posted by Heidi View Post
    wich one does not belonq??? and why???


    72 27 342 343
    One more possibility
    make pairs
    if 1st number 72 then next number is 27(that is interchange of digits)
    similarly
    if 1st number is 342 second should be 243 (again interchange of digits) not 343 hence 343 should not belong to the sequence
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  4. #4
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    mr fantastic's Avatar
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    Quote Originally Posted by Heidi View Post
    wich one does not belonq??? and why???


    72 27 342 343
    *snort* Clearly 342 doesn't belong ...... The other three numbers all have a factor that's the cube of a prime number

    By the way ...... the snort is me being facetious. There are also excellent reasons why

    72 doesn't belong.

    27 doesn't belong.

    I find these types of questions quite ridiculous.
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  5. #5
    Grand Panjandrum
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    Quote Originally Posted by mr fantastic View Post
    *snort* Clearly 342 doesn't belong ...... The other three numbers all have a factor that's the cube of a prime number

    By the way ...... the snort is me being facetious. There are also excellent reasons why

    72 doesn't belong.

    27 doesn't belong.

    I find these types of questions quite ridiculous.
    Exactly, but we can't encourage the student to tell their teacher that, as they will just be poonished for being right

    RonL
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