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Try entering different sets of numbers in the number pyramids. How does the total at the top change?
Think of a number and follow the machine's instructions... I know what your number is! Can you explain how I know?
Crosses can be drawn on number grids of various sizes. What do you notice when you add opposite ends?
Create some shapes by combining two or more rectangles. What can you say about the areas and perimeters of the shapes you can make?
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?
Surprising numerical patterns can be explained using algebra and diagrams...
When number pyramids have a sequence on the bottom layer, some interesting patterns emerge...
Where should you start, if you want to finish back where you started?
Play around with the Fibonacci sequence and discover some surprising results!
Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...
Think of two whole numbers under 10, and follow the steps. I can work out both your numbers very quickly. How?
The answer is $5x+8y$... What was the question?
A collection of short problems on creating algebraic expressions.
The Number Jumbler can always work out your chosen symbol. Can you work out how?