Question 1200860
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If this problem came from your teacher, ask the teacher.


If it came from the other source, which you may ask, ask the source.



If it is found somewhere in the Internet, and you can not ask the source, 
we are not responsible for it, since we do not control everything in the Internet.



If you can interpret it in a way to get interesting Math problem, (try to) do it.



If you can not, forget about this problem.



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Actually,  in  Geometry,  there is a standard name for a  " straight line which terminates at one point ".  This name is  " a ray ".


A straight line,  in the strict sense of  Geometry,  does not terminate anywhere - it is infinite in both directions.



Had I formulate this problem, I would do it in such a way that 
only one interpretation be possible, as it should be for any true Math problem.



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Probably,  they want to say that  12  different rays are released from one point on a plane.
After that,  they want to ask,  how many angles less than  180  degrees are formed.



If so,  then each  (unordered)  pair of the rays form exactly one such angle, 
and different angles are formed by different pairs of rays,
so the number of all such angles is    {{{(12*11)/2}}} = 6*11 = 66,
exactly as the number of all different unordered pairs of the rays.



But it is my interpretation and reformulation,  so I can not guarantee that they mean exactly the same.

I do not read in their minds.