Asked • 06/28/20

What is the probability of a point in an infinite 3-D space of being within the region bounded by 3 randomly placed and oriented planes?

Each plane is denoted by Ax + By + Cz + D = 0, where A, B, C, D are real numbers (specific to that plane). --

I suspect the answer is P=0, since the area outside any bounded region must exceed that inside. But how to prove that?

2 Answers By Expert Tutors

By:

Nitin P. answered • 06/28/20

Tutor
4.9 (134)

Machine Learning Engineer - UC Berkeley CS+Math Grad

Rabie R. answered • 06/28/20

Tutor
5.0 (255)

Experienced, Patient and Knowledgeable Math Tutor

Nitin P.

We don't care about the distribution of the points, because they're already fixed in space and deterministic. We care about what happens when we randomly place the planes.
Report

06/28/20

Rabie R.

Your answer makes sense if the question is reformulated. However, as the question is formulated now, there are issues with it: 1) you need a distribution. The points are fixed, but are all points equally likely outcomes when you're picking a point? 2) The question asks about being in a region "bounded" by 3 planes. The question doesn't specify a distribution, so assuming all points are equally likely to be picked, you can never get a 1/8 probability of being inside a finite volume out of a domain with an infinite volume.
Report

06/28/20

Still looking for help? Get the right answer, fast.

Ask a question for free

Get a free answer to a quick problem.
Most questions answered within 4 hours.

OR

Find an Online Tutor Now

Choose an expert and meet online. No packages or subscriptions, pay only for the time you need.