Question 1025560
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We use π to calculate area of circles. The ancient Egyptians had a method, documented around 1650 BC in the 
Rhind Mathematical Papyrus, of calculating the area of a circle without π as we now know it. 
They took a square with side length equal to the diameter of the circle (Figure 1), trisected each side and 
removed the corner triangles (Figure 2) and used the remaining octagonal shape (Figure 3) to approximate 
the area of the circle. Using this method, what would be the calculated area of a circle with diameter 9 units?

 https://www.mathcounts.org/sites/default/files/u5328/Egyptian%20Circle.jpg
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<pre>
{{{9^2}}} - {{{4*((3*3)/2)}}} = 81 - 2*9 = 63 sq.units against {{{pi*4.5^2}}} = 63.585 sq. inits.
</pre>