Given 11 points, of which 5 lie on one circle, other than these 5, no 4 lie on one circle. Then the maximum number of circles that can be drawn so that each contains atleast three of the given points is

Explanation

We need at least three points to draw a circle that passes through them.


Now, number of circles formed out of 11 points by taking three points at a time `=^11C_3=165`


Number of circles formed out of 5 points by taking three points at a time `=^5C_3=10`
It is given that 5 points lie on one circle.


Required number of circles

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