Being resilient

  • Multiples Sudoku
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    Multiples Sudoku

    Age
    11 to 14
    Challenge level
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    Each clue in this Sudoku is the product of the two numbers in adjacent cells.

  • How much can we spend?
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    How Much Can We Spend?

    Age
    11 to 14
    Challenge level
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    A country has decided to have just two different coins. Which totals can be made? Is there a largest total that cannot be made? How do you know?

  • Can you Make 100?
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    Can You Make 100?

    Age
    11 to 14
    Challenge level
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    How many ways can you find to put in operation signs (+, −, ×, ÷) to make 100?

  • Number Daisy
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    Number Daisy

    Age
    11 to 14
    Challenge level
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    Can you find six numbers to go in the daisy from which you can make all the numbers from 1 to a number bigger than 25?

  • Add to 200
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    Add to 200

    Age
    11 to 14
    Challenge level
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    By selecting digits for an addition grid, what targets can you make?

  • Forwards Add Backwards
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    Forwards Add Backwards

    Age
    11 to 14
    Challenge level
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    What happens when you add a three digit number to its reverse?

  • About Average
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    About Average

    Age
    11 to 14
    Challenge level
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    Can you find sets of numbers which satisfy each of our mean, median, mode and range conditions?

  • Legs Eleven
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    Legs Eleven

    Age
    11 to 14
    Challenge level
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    Take any four digit number. Move the first digit to the end and move the rest along. Now add your two numbers. Did you get a multiple of 11?

  • Where can we visit?
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    Where Can We Visit?

    Age
    11 to 14
    Challenge level
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    Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: ×2 and -5. What do you think?

  • 1 Step 2 Step
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    1 Step 2 Step

    Age
    11 to 14
    Challenge level
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    Liam's house has a staircase with 12 steps. He can go down the steps one at a time or two at time. In how many different ways can Liam go down the 12 steps?