Monday, July 13, 2009

Problem of The day 13.07.09

On a circle 26 equidistant points are marked. these points are joined to form a triangles. Of the triangles formed, how many of them will have their circumcenter on one of their sides.?

A) 318 B) 312 C) 288 d) 624 e) None of these

9 comments:

  1. according to given condn...d triangles shld be "rightangled" so......right angle is only formed when one f d side is a diameter..den in such case..
    option(a) might be the answer..318

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  2. @Anup, your reasoning is right, you have made a calculation error.

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  3. the triangle must be right triangle and hence two points chosen must form the diameter.
    13 diametrically opposite points can be chosen and for each of these points we have 24 other points remaining,hence it shud be 24x13=312

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  4. If the points are equidistant then how can they form right angled triangle, why cant they form equilateral triangle

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  5. 26*24 = 624

    am i right dude?

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