Explaining, convincing and proving

  • Far Horizon
    problem
    Favourite

    Far Horizon

    Age
    14 to 16
    Challenge level
    filled star filled star filled star

    An observer is on top of a lighthouse. How far from the foot of the lighthouse is the horizon that the observer can see?

  • Harmonic Triangle
    problem
    Favourite

    Harmonic Triangle

    Age
    14 to 16
    Challenge level
    filled star filled star filled star

    Can you see how to build a harmonic triangle? Can you work out the next two rows?

  • LCM Sudoku
    problem
    Favourite

    LCM Sudoku

    Age
    14 to 16
    Challenge level
    filled star filled star filled star

    Here is a Sudoku with a difference! Use information about lowest common multiples to help you solve it.

  • Partly Circles
    problem
    Favourite

    Partly Circles

    Age
    14 to 16
    Challenge level
    filled star filled star filled star

    What is the same and what is different about these circle questions? What connections can you make?

  • Fit for photocopying
    problem
    Favourite

    Fit for Photocopying

    Age
    14 to 16
    Challenge level
    filled star filled star filled star

    Explore the relationships between different paper sizes.

  • Difference Sudoku
    problem
    Favourite

    Difference Sudoku

    Age
    14 to 16
    Challenge level
    filled star filled star filled star

    Use the differences to find the solution to this Sudoku.

  • Mega Quadratic Equations
    problem
    Favourite

    Mega Quadratic Equations

    Age
    14 to 18
    Challenge level
    filled star empty star empty star

    What do you get when you raise a quadratic to the power of a quadratic?

  • There's a limit
    problem
    Favourite

    There's a Limit

    Age
    14 to 18
    Challenge level
    filled star empty star empty star

    Explore the continued fraction: 2+3/(2+3/(2+3/2+...)) What do you notice when successive terms are taken? What happens to the terms if the fraction goes on indefinitely?

  • Unit Interval
    problem
    Favourite

    Unit Interval

    Age
    14 to 18
    Challenge level
    filled star empty star empty star

    Take any two numbers between 0 and 1. Prove that the sum of the numbers is always less than one plus their product?

  • Iffy logic
    problem
    Favourite

    Iffy Logic

    Age
    14 to 18
    Challenge level
    filled star empty star empty star

    Can you rearrange the cards to make a series of correct mathematical statements?