Ratio and proportion

  • Timber!
    problem

    Timber!

    Age
    7 to 11
    Challenge level
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    How can the school caretaker be sure that the tree would miss the school buildings if it fell?
  • Nutty Mixture
    problem

    Nutty Mixture

    Age
    7 to 11
    Challenge level
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    Use the ratio of cashew nuts to peanuts to find out how many peanuts Rachel has. What would the ratio be if Rachel and Marianne mixed their bags?

  • Number the Sides
    problem

    Number the Sides

    Age
    7 to 11
    Challenge level
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    The triangles in these sets are similar - can you work out the lengths of the sides which have question marks?
  • Rod Ratios
    problem

    Rod Ratios

    Age
    7 to 11
    Challenge level
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    Use the Cuisenaire rods environment to investigate ratio. Can you find pairs of rods in the ratio 3:2?

  • Retiring to paradise
    problem

    Retiring to Paradise

    Age
    11 to 14
    Challenge level
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    When Charlie retires, he's looking forward to the quiet life, whereas Alison wants a busy and exciting retirement. Can you advise them on where they should go?

  • Tray Bake
    problem

    Tray Bake

    Age
    11 to 14
    Challenge level
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    My recipe is for 12 cakes - how do I change it if I want to make a different number of cakes?
  • Toad in the Hole
    problem

    Toad in the Hole

    Age
    11 to 14
    Challenge level
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    Is it cheaper to cook a meal from scratch or to buy a ready meal? What difference does the number of people you're cooking for make?
  • Straw Scaffold
    problem

    Straw Scaffold

    Age
    11 to 14
    Challenge level
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    Build a scaffold out of drinking-straws to support a cup of water
  • Off the Cuff
    problem

    Off the Cuff

    Age
    11 to 14
    Challenge level
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    Can you work out the ratio of shirt types made by a factory, if you know the ratio of button types used?

  • Double Cover
    problem

    Double Cover

    Age
    11 to 14
    Challenge level
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    Weekly Problem 3 - 2007
    What is the ratio of the area of the table covered twice, to the uncovered area?