February 2015 - Circles Inside Circles

Start with a big circle. Draw two circles with half the radius inside it, so that they touch at the centre of the original circle. Draw a smaller circle tangent to all three. Draw a still smaller circle tangent to the three circles inside the large one. If the area of the smallest circle is 1, what is the area of the biggest circle?

The deadline has passed. You can see the answer or go to the Hall of Fame.

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