Geometry: An Interactive Journey to Mastery

Lesson 25: Playing with Geometric Probability

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Even if no explicit values are given in a problem, determining an explicit value for such a ratio might

still be possible.

 You break a stick into two pieces at some point chosen at random along its length. What is the probability

that the left piece is longer than the right piece?

 A bus arrives at a particular station every 15 minutes. Each bus waits precisely 4 minutes before leaving.

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minute for the bus to leave?

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than 3 minutes to see one arrive?

 A sphere sits snugly in a cube. A point inside the cube is chosen at random. What is the probability that this

point also lies inside the sphere?

 A circular pond sits in Mr. Foiglesplot’s back yard. The pond has radius 5 feet, and the yard is rectangular,

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the pond?

Problems