Inequalities

  • In Between
    problem
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    In Between

    Age
    16 to 18
    Challenge level
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    Can you find the solution to this algebraic inequality?
  • Discrete Trends
    problem
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    Discrete Trends

    Age
    16 to 18
    Challenge level
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    Find the maximum value of n to the power 1/n and prove that it is a maximum.

  • Random inequalities
    problem
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    Random Inequalities

    Age
    16 to 18
    Challenge level
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    Can you build a distribution with the maximum theoretical spread?
  • Two Cubes
    problem

    Two Cubes

    Age
    14 to 16
    Challenge level
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    Two cubes, each with integral side lengths, have a combined volume equal to the total of the lengths of their edges. How big are the cubes? [If you find a result by 'trial and error' you'll need to prove you have found all possible solutions.]
  • Reciprocals
    problem

    Reciprocals

    Age
    16 to 18
    Challenge level
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    Prove that the product of the sum of n positive numbers with the sum of their reciprocals is not less than n^2.
  • Classical Means
    problem

    Classical Means

    Age
    16 to 18
    Challenge level
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    Use the diagram to investigate the classical Pythagorean means.
  • Fracmax
    problem

    Fracmax

    Age
    14 to 16
    Challenge level
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    Find the maximum value of 1/p + 1/q + 1/r where this sum is less than 1 and p, q, and r are positive integers.
  • Jute bag with marbles of different colours spilling out.
    problem

    Inequalities

    Age
    11 to 14
    Challenge level
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    A bag contains 12 marbles. There are more red than green but green and blue together exceed the reds. The total of yellow and green marbles is more than the total of red and blue. How many of each colour there are in the bag?