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shilpaqueen
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How many triangles can be formed using 8 points in a given plane when 3 points out of 8 are collinier
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Rahul@gurome
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By joining any 3 non collinear points, we get a triangle.
Had all 8 points been non collinear, the number of ways triangles would have been 8C3 which is 56.
But since 3 points are collinear, they will not make a triangle.
So the number of triangles we can have is 56 - 1 = 55.
Had all 8 points been non collinear, the number of ways triangles would have been 8C3 which is 56.
But since 3 points are collinear, they will not make a triangle.
So the number of triangles we can have is 56 - 1 = 55.
Rahul Lakhani
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Quant Expert
Gurome, Inc.
https://www.GuroMe.com
On MBA sabbatical (at ISB) for 2011-12 - will stay active as time permits
1-800-566-4043 (USA)
+91-99201 32411 (India)
