1. Slide 6- 1 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. Active Learning Lecture Slides For use with Classroom Response Systems Elementary Statistics Eleventh Edition and the Triola Statistics Series by Mario F. Triola Chapter 6: Normal Probability Distributions

2. Slide 6- 2 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. Assume that the weight loss for the first month of a diet program varies between 6 pounds and 12 pounds, and is spread evenly over the range of possibilities, so that there is a uniform distribution. Find the probability of losing less than 10 pounds. A. 5/7 B. 2/3 C. 1/3 D. 1/6

3. Slide 6- 3 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. Assume that the weight loss for the first month of a diet program varies between 6 pounds and 12 pounds, and is spread evenly over the range of possibilities, so that there is a uniform distribution. Find the probability of losing less than 10 pounds. A. 5/7 B. 2/3 C. 1/3 D. 1/6

4. Slide 6- 4 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. A recent survey based upon a random sample of 420 voters, predicted that the Independent candidate for the mayoral election will get 24% of the vote, but he actually gets 27%. Can you conclude that the survey was done incorrectly? A. Yes B. No

5. Slide 6- 5 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. A recent survey based upon a random sample of 420 voters, predicted that the Independent candidate for the mayoral election will get 24% of the vote, but he actually gets 27%. Can you conclude that the survey was done incorrectly? A. Yes B. No

6. Slide 6- 6 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. If Z is a standard normal variable, find the probability that Z lies between 0.7 and 1.98. A. 0.2175 B. –0.2181 C. 1.7341 D. 0.2181

7. Slide 6- 7 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. If Z is a standard normal variable, find the probability that Z lies between 0.7 and 1.98. A. 0.2175 B. –0.2181 C. 1.7341 D. 0.2181

8. Slide 6- 8 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. A final exam in Math 160 has a mean of 73 with a standard deviation of 7.8. If 24 students are randomly selected, find the probability that the mean of their test scores is less than 70. A. 0.1006 B. 0.0301 C. 0.9699 D. 0.0278

9. Slide 6- 9 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. A final exam in Math 160 has a mean of 73 with a standard deviation of 7.8. If 24 students are randomly selected, find the probability that the mean of their test scores is less than 70. A. 0.1006 B. 0.0301 C. 0.9699 D. 0.0278

10. Slide 6- 10 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. For a normal distribution with n = 53 and p =.7, state whether or not it is suitable to use the normal distribution as an approximation to the binomial distribution? A. Normal approximation is not suitable. B. Normal approximation is suitable.

11. Slide 6- 11 Copyright © 2010, 2007, 2004 Pearson Education, Inc. All Rights Reserved. For a normal distribution with n = 53 and p =.7, state whether or not it is suitable to use the normal distribution as an approximation to the binomial distribution? A. Normal approximation is not suitable. B. Normal approximation is suitable.