List

Creating and manipulating linear and quadratic expressions - Stage 3

Special Numbers
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Special numbers

Age
11 to 14
Challenge level
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My two digit number is special because adding the sum of its digits to the product of its digits gives me my original number. What could my number be?

Number Pyramids
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Number pyramids

Age
11 to 14
Challenge level
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Try entering different sets of numbers in the number pyramids. How does the total at the top change?

More Number Pyramids
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More number pyramids

Age
11 to 14
Challenge level
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When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...

Your number is...
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Your number is...

Age
7 to 14
Challenge level
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Think of a number and follow the machine's instructions... I know what your number is! Can you explain how I know?
Harmonic Triangle
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Harmonic triangle

Age
14 to 16
Challenge level
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Can you see how to build a harmonic triangle? Can you work out the next two rows?
Crossed Ends
problem
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Crossed ends

Age
11 to 14
Challenge level
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Crosses can be drawn on number grids of various sizes. What do you notice when you add opposite ends?
Always a multiple?
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Always a multiple?

Age
11 to 14
Challenge level
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Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...
Perimeter Expressions
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Perimeter expressions

Age
11 to 14
Challenge level
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Create some shapes by combining two or more rectangles. What can you say about the areas and perimeters of the shapes you can make?
Beach Huts
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Beach huts

Age
11 to 14
Challenge level
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Can you figure out how sequences of beach huts are generated?
Reversals
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Reversals

Age
11 to 14
Challenge level
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Where should you start, if you want to finish back where you started?
Fibonacci Surprises
problem
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Fibonacci surprises

Age
11 to 14
Challenge level
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Play around with the Fibonacci sequence and discover some surprising results!

Puzzling Place Value
problem
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Puzzling place value

Age
14 to 16
Challenge level
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Can you explain what is going on in these puzzling number tricks?