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Have You Got It?

Can you explain the strategy for winning this game with any target?

Counting Factors

Is there an efficient way to work out how many factors a large number has?

Is There a Theorem?

Draw a square. A second square of the same size slides around the first always maintaining contact and keeping the same orientation. How far does the dot travel?

Hidden Rectangles

Age 11 to 14
Challenge Level


Picture of rectangles


Rectangles are considered different if they vary in size or have different locations.

How many different rectangles can be drawn along the lines on a chessboard?

How many of the rectangles are squares?

What happens on an n by n board?