The younger children calculated π using
Buffon's needle approach with 94 tries -- π = 3.836734694
Counting the number of grid points in a circle:
For radius 6 --- we counted 108 grid points. giving an approximation of π = 3.
But we should have actually seen 113 points in the circle.
For radius 11. For the radius of 6, we saw 529 - 148 = 381 points, giving us an approximation of π = 3.148760.
The elder children were calculating π using the Madhava Formula.
We came upto the approximation of π = 3.0702560
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