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## 'Squaring the Circle' printed from http://nrich.maths.org/

Bluey - green squares, white squares, transparent squares with a
few odd bits of shapes around the perimeter.

But, how many squares are there of each type in the complete
circle?

Study the picture and make an estimate. Note the totals before
embarking on a more rigorous audit of what is there.

How accurate was your estimate?

Can you give an upper and a lower bound to your estimate?

If the blue-green squares are of 1 and 1.5 units of length, the
white squares of 1.5 units and the transparent squares 1.75 units
of length - how "big" is the circular part of the pavement?

If the circular part was used as the design for a Roll- a- Penny
stall which paid out on pennies successfully rolling fully into a
transparent square: what is the probability of winning on this
layout? You might like to think about the best and worst case.