Prentice Hall Geometry

Algebra Find the probability that coordinate x of a point chosen at random on eh k bar  satisfies the inequality.

A number line from 0 to 10 has increments lettered A through K.

  1. 2 less than or equal to . x less than or equal to 8
  2. 2 x less than or equal to 8
  3. 5 less than or equal to . 11 minus 6 x
  4. 1 half , x minus . 5 greater than 0
  5. 2 less than or equal to . 4 x less than or equal to 3
  6. negative 7 less than or equal to . 1 minus . 2 x less than or equal to 1
  7. One type of dartboard is a square of radius 10 in. You throw a dart and hit the target. What is the probability that the dart lies within square root of 10  in. of the square's center?
  8. Games To win a prize at a carnival game, you must toss a quarter, so that it lands entirely within a circle as shown below. Assume that the center of a tossed quarter is equally likely to land at any point within the 8-in. square.

    A square with sides of 8 inches contains a circle with radius 1 inch. Inside the circle, a quarter touching one side is centered 15 over 32 inches from the circle, on a concentric circle with radius 17 over 32 inches.

    1. What is the probability that the quarter lands entirely in the circle in one toss?
    2. Reasoning On average, how many coins must you toss to win a prize? Explain.
  9. Traffic Patterns The traffic lights at Fourth and State Streets repeat themselves in 1-min cycles. A motorist will face a red light 60% of the time. Use this information to estimate how long the Fourth Street light is red during each 1-min cycle.
  10. You have a 4-in. straw and a 6-in. straw. You want to cut the 6-in. straw into two pieces so that the three pieces form a triangle.
    1. If you cut the straw to get two 3-in. pieces, can you form a triangle?
    2. If the two pieces are 1 in. and 5 in., can you form a triangle?
    3. If you cut the straw at a random point, what is the probability that you can form a triangle?
  11. Target Game Assume that a dart you throw will land on the 12 in.-by-12 in. square dartboard and is equally likely to land at any point on the board. The diameter of the center circle is 2 in., and the width of each ring is 1 in.

    A target is a gray square containing concentric circles at its center, colored blue, yellow, and red, from inside out.

    1. What is the probability of hitting either the blue or yellow region?
    2. What is the probability the dart will not hit the gray region?

C Challenge

  • 44. Graphing Calculator A circular dartboard has radius 1 m and a yellow circle in the center. Assume you hit the target at a random point. For what radius of the yellow center region would P(hitting yellow) equal each of the following? Use the table feature of a calculator to generate all six answers. Round to the nearest centimeter.
    1. 0.2
    2. 0.4
    3. 0.5
    4. 0.6
    5. 0.8
    6. 1.0
  • You and your friend agree to meet for lunch between 12 P.M. and 1 P.M. Each of you agrees to wait 15 min for the other before giving up and eating lunch alone. If you arrive at 12:20, what is the probability you and your friend will eat lunch together?

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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