1. 1-6 Probability Hubarth Algebra II

2. Ex. 1 Finding Experimental probability A player hit the bull’s eye on a circular dartboard 8 times out of 50. Find the experimental probability that the player hits the bull’s eye. P(bull’s eye) = = 0.16, or 16% 8 50

3. Describe a simulation you could use that involves flipping a coin to find the experimental probability of guessing exactly 2 answers out of 6 correctly on a true-false quiz. Getting heads with a flip of a coin has the same probability as guessing the correct answer to a question on a true-false test. So, let heads represent a correct answer and tails represent an incorrect answer. To simulate guessing the answers for a six-question true-false test, flip a coin six times. Record the number of heads. Repeat 100 times. Count to see how many times heads came up exactly twice. Divide this number by 100. The result is the experimental probability that the simulation gives for guessing 2 correct answers out of 6. Ex. 2 Using a Simulation

4. Ex. 3 Finding Theoretical Probability Find the theoretical probability of rolling a multiple of 3 with a number cube. To roll a multiple of 3 with a number cube, you must roll 3 or 6. 2626 6 equally likely outcomes are in the sample space. 2 outcomes result in a multiple of 3. 1313 =

5. Ex. 4 Real-World Connection Brown is a dominant eye color for human beings. If a father and mother each carry a gene for brown eyes and a gene for blue eyes, what is the probability of their having a child with blue eyes? B b B BB Bb b Bb bb Gene from Father Gene from Mother Let B represent the dominant gene for brown eyes. Let b represent the recessive gene for blue eyes. The sample space contains four equally likely outcomes {BB, Bb, Bb, bb}. 1414 The outcome bb is the only one for which a child will have blue eyes. So, P(blue eyes) =. 1414 The theoretical probability that the child will have blue eyes is, or 25%.

6. Ex. 5 Finding Geometric Probability 2 5 10 20 Suppose all the circular dartboard shown at the right are equally likely to be hit by a dart you have thrown. Find the probability of Scoring at least ten points. P(at least 10 points). The width of each ring is r

7. Practice 1. In the 2006 Rose Bowl, USC’s quarterback completed 29 of 40 passes. Find the experimental probability. 2. Find the theoretical probability of getting a prime number when you roll a number cube. 3. Using the information in example 4, what is the theoretical probability of a child having brown eyes. B b B BBB Bb B Bb bb Gene from Father Gene from Mother 4. Using the dartboard from example 5, Find each probability. a. P(scoring 20 points)b. P(scoring 5 points)