Geometry: An Interactive Journey to Mastery

Lesson 25: Playing with Geometric Probability

Playing with Geometric Probability

Lesson 25

Topics

x The theory of geometric probability.

x Examples, and a word of caution.

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x geometric probability: This principle states that if a point of a

region B is chosen at random, then the probability that it lands

in a subregion ALVDVIROORZVͼ௘6HH)LJXUH௘ͽ

probability = areaareaAb.

This seems to be an intuitively valid notion.

Summary

The theory of geometric probability allows us to use geometric intuition to solve problems of chance even if, at

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principle of geometric probability and apply it to a variety of situations.

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Q is the midpoint of RT, and S is the midpoint of QT. A point is picked at random on RT. What are the

chances that it lands in RS?

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Probability =^3344 xx.

A

B

Figure 25.1

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Figure 25.2