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Math Help - Jill asks each of her classmates to choose a number....HELP!!

  1. #1
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    Jill asks each of her classmates to choose a number....HELP!!

    I'm taking a math theory class and am in over my head. I'm making it but am completely stumped by this question. "Jill asks each of her classmates to choose a number, then multiply the number by -3, add 2 to the product, multiply the result by -2, and then subtract 14. Finally, each student is asked to divide the result by 6 and record the answer. When Jill gets their answers, she adds 3 to it in her head and announces the number that classmate originally chose. How did Jill know to add 3 to ach answer?"

    Totally frustrated!! Can anyone help?
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  2. #2
    Senior Member MacstersUndead's Avatar
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    Re: Jill asks each of her classmates to choose a number....HELP!!

    Let the number the classmate chooses be n.

    Following through the specified transformations we get n -> -3n -> -3n + 2 -> 6n-4 -> 6n - 18 -> n-3

    Adding 3 to n-3 gives n, the original number.
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