Prentice Hall Geometry

See Problems 3 and 4.

A point in the figure is chosen at random. Find the probability that the point lies in the shaded region.

  1. A circle has two radius lines measuring 3 inches with a shaded sector between them within arc measuring 80 degrees.
  2. A shaded square with sides of 5 meters has a square removed from the center with sides of 3 meters.
  3. A shaded circle with diameter 6 feet has a circle removed from the center with diameter 4 feet.
  4. A square with sides of 12 inches has four congruent shaded circles inscribed inside, each circle touching two sides of the square.

Target Game A target with a diameter of 14 cm has 4 scoring zones formed by concentric circles. The diameter of the center circle is 2 cm. The width of each ring is 2 cm. A dart hits the target at a random point. Find the probability that it will hit a point in the indicated region.

A target consists of concentric rings colored white, red, blue, and yellow, from inside out.

  1. the center region
  2. the blue region
  3. either the blue or red region
  4. any region

B Apply

  1. Points M and N are on z b bar  with M between Z and N. ZM equals 5 comma . n b equals 9 comma  and z b equals 20 .  A point on z b bar  is chosen at random. What is the probability that the point is on m n bar , question mark
  2. b z bar  contains m n bar  and b z equals 20 .  A point on b z bar  is chosen at random. The probability that the point is also on m n bar  is 0.3, or 30%. Find m n bar , .
  3. Think About a Plan Every 20 min from 4:00 p.m. to 7:00 p.m., a commuter train crosses Boston Road. For 3 min, a gate stops cars from crossing over the tracks as the train goes by. What is the probability that a motorist randomly arriving at the train crossing during this time interval will have to stop for a train?
    • How can you represent the situation visually?
    • What ratio can you use to solve the problem?
  4. Reasoning Suppose a point in the regular pentagon is chosen at random. What is the probability that the point is not in the shaded region? Explain.

    A pentagon has five radius lines forming five triangles, with two adjacent triangles shaded.

  5. Commuting A bus arrives at a stop every 16 min and waits 3 min before leaving. What is the probability that a person arriving at the bus stop at a random time has to wait more than 10 min for a bus to leave?
  6. Astronomy Meteorites (mostly dust-particle size) are continually bombarding Earth. The surface area of Earth is about 65.7 million mi squared , .  The area of the United States is about 3.7 million mi squared , .  What is the probability that a meteorite landing on Earth will land in the United States?
  7. Reasoning What is the probability that a point chosen at random on the circumference of circle dot  C lies on modified eh b with frown above , question mark  Explain how you know.

    A circle has perpendicular radius lines extending to A and B on the circle, respectively.

  8. Writing Describe a real-life situation in which you would use geometric probability.

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Table of Contents

Prentice Hall Geometry Chapter 1 Tools of Geometry Chapter 2 Reasoning and Proof Chapter 3 Parallel and Perpendicular Lines Chapter 4 Congruent Triangles Chapter 5 Relationships Within Triangles Chapter 6 Polygons and Quadrilaterals Chapter 7 Similarity Chapter 8 Right Triangles and Trigonometry Chapter 9 Transformations Chapter 10 Area Chapter 11 Surface Area and Volume Chapter 12 Circles Skills Handbook Reference Visual Glossary Selected Answers Index Acknowledgments