perplexus.info :: Probability : Triangular Cubes

Triangular Cubes (Posted on 2004-12-04)

Three points have been chosen randomly from the vertices of a cube. What is the probability that they form (a) an acute triangle; (b) a right triangle?

See The Solution Submitted by Erik O.

Rating: 3.0000 (2 votes)

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Solution

| Comment 1 of 11

There are C(8,3) = 56 possible triangles. Eight of these are equilateral triangles and the other 48 are right triangles. Threfore,

a) 1/7

b) 6/7

Posted by Bractals on 2004-12-04 17:21:28

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