Conjecturing and generalising

There are 405 NRICH Mathematical resources connected to Conjecturing and generalising
At right angles
problem
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At right angles

Age
14 to 16
Challenge level
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Can you decide whether two lines are perpendicular or not? Can you do this without drawing them?
Mystic Rose
problem
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Mystic rose

Age
14 to 16
Challenge level
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Use the animation to help you work out how many lines are needed to draw mystic roses of different sizes.
Ip Dip
problem
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Ip dip

Age
5 to 11
Challenge level
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"Ip dip sky blue! Who's 'it'? It's you!" Where would you position yourself so that you are 'it' if there are two players? Three players ...?

Chocolate
problem
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Chocolate

Age
7 to 14
Challenge level
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There are three tables in a room with blocks of chocolate on each. Where would be the best place for each child in the class to sit if they came in one at a time?

Odd Differences
problem
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Odd differences

Age
14 to 16
Challenge level
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The diagram illustrates the formula: 1 + 3 + 5 + ... + (2n - 1) = n² Use the diagram to show that any odd number is the difference of two squares.
Fair Shares?
problem
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Fair shares?

Age
14 to 16
Challenge level
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A mother wants to share a sum of money by giving each of her children in turn a lump sum plus a fraction of the remainder. How can she do this in order to share the money out equally?
Flashing Lights
problem
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Flashing lights

Age
7 to 11
Challenge level
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Norrie sees two lights flash at the same time, then one of them flashes every 4th second, and the other flashes every 5th second. How many times do they flash together during a whole minute?
Shadow Play
problem
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Shadow play

Age
5 to 7
Challenge level
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Here are shadows of some 3D shapes. What shapes could have made them?

Cubes within Cubes revisited
problem
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Cubes within cubes revisited

Age
11 to 14
Challenge level
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Imagine starting with one yellow cube and covering it all over with a single layer of red cubes, and then covering that cube with a layer of blue cubes. How many red and blue cubes would you need?
Mirror, mirror...
problem
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Mirror, mirror...

Age
11 to 14
Challenge level
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Explore the effect of reflecting in two parallel mirror lines.