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I'm confused on my calculations on analytic geometry with probability. Things I learned on these were messed up since I was a newbie on these subjects. Here's my problem:
Three points are chosen uniformly at random from the perimeter of circle. The probability that the triangle formed by these is acute can be expressed as $a/b$ where $a$ and $b$ are coprime positive integers. What is the value of $a+b$?
You may provide explanations so I would know how it was solved. Thank you