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Square Areas

Can you work out the area of the inner square and give an explanation of how you did it?

Square Pegs

Which is a better fit, a square peg in a round hole or a round peg in a square hole?

Lying and Cheating

Follow the instructions and you can take a rectangle, cut it into 4 pieces, discard two small triangles, put together the remaining two pieces and end up with a rectangle the same size. Try it!

Not So Little X

Age 11 to 14 Challenge Level:

Two circles are enclosed by a rectangle 12 units by x units.

The distance between the centres of the two circles is x/3 units.

How big is x?

Circles in the box
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.
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