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Homework Help: Weird GRE symbol problem

  1. Jan 21, 2009 #1
    1. The problem statement, all variables and given/known data

    This problem asks you to compare two values and say whether one is greater, they are the same, or the problem does not give you enough information to answer the question. In this question they give you a symbol, in this case "+" and then define what it does to a number.

    The problem states:

    If N is a positive integger, than N+ denotes a number such that N<N+<N+1

    Then it asks you to compare:




    The correct answer is "The relationship cannot be determined from the information given"

    3. The attempt at a solution

    I have no clue how to even start with this problem. I don't understand how to translate their meaning for "+" into an operation on those numbers.
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jan 21, 2009 #2
    This is funny notation no doubt. But you can change the notation. Is this problem simpler?

    Let x, y, and z be numbers such that 20 < x < 21, 4 < y < 5, 5 < z < 6. Compare x/y to z.
  4. Jan 21, 2009 #3


    Staff: Mentor

    According to the definition you provided,
    N+ satisfies the relationship N < N+ < N + 1, where N is a positive integer. IOW, N+ is a number between N and N + 1. (It's helpful to add some spaces to make this expression more readable and maybe more understandable.)

    In your problem, 20+ is between 20 and 21, and 4+ is between 4 and 5.
    What can you say about the quotient 20+ / 4+? What's the largest value of this quotient? What's the smallest value? (It's 4.)

    Compare your result with 5+, which you should realize by now as being between 5 and 6.
  5. Jan 21, 2009 #4
    Oh i see now. thanks guys
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