From: rusin@vesuvius.math.niu.edu (Dave Rusin) Newsgroups: sci.math Subject: Re: A couple of probably basic questions... Date: 10 Jul 1996 05:26:08 GMT In article <4r0dvf$62c@gerry.cc.keele.ac.uk>, P.H. Johnson wrote: >Q1. I have 3 triangles and I need to know the dimensions of the largest >sphere (diameter or volume) that could fit through each. > >The triangle dimensions are as follows: > > Side 1 Side 2 Side 3 >Triangle 1 112 109 108 >Triangle 2 96 92 113 >Triangle 3 112 116 110 If I understand correctly you seek the diameter of the (largest possible) inscribe circle in these triangles. I hope I'm remembering correctly when I give this formula: if the sides are a, b, and c, let s = (a+b+c)/2; then the radius of the inscribed triangle is sqrt((s-a)(s-b)(s-c)/s) and of course the diameter is twice that. For example, Triangle 1 gives a diameter of about 63.268. dave