Click here to win prizes by solving the puzzle Advent calendar.
Click here to win prizes by solving the puzzle Advent calendar.


Sunday Afternoon Maths XII

 Posted on 2014-05-11 

Unit octagon

The diagram shows a regular octagon with sides of length 1. The octagon is divided into regions by four diagonals. What is the difference between the area of the hatched region and the area of the region shaded grey?

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Largest triangle

What is the largest area triangle which has one side of length 4cm and one of length 5cm?

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Which is largest, the red or the blue area?

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