The number of circles that can be drawn out of 10 points of which 7 are collinear is Choose the correct choice from the following choices
A) 130
B) 85
C) 45
D) Cannot be determined
E) None of these
Solution   For drawing a circle we need 3 non collinear points.This can be done in:   3C3 + 3C2 × 7C1 + 3C1 × 7C2 = 1 + 21 + 63= 
<gadget id="calculator">1 + 21 + 63</gadget>
<output>85</output>
85. Answer 85
<result>B</result>
The number of circles that can be drawn out of 10 points of which 7 are collinear is