SOLUTION: How many triangles are determined by 20 points if no three of them are in a line?

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Question 439770: How many triangles are determined by 20 points if no three of them are in a line?
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Choose three different points out of 20.

20C3 = 20*19*18/3! = 1140