Transcript les4e_alq_05ac

Active Learning Lecture Slides
For use with Classroom Response Systems
Chapter 5: Normal Probability Distributions
Elementary Statistics:
Picturing the World
Fourth Edition
by Larson and Farber
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 4- 1
Find the probability using the standard
normal distribution.
P(z < 1.49)
A. 0.9319
B. 0.0681
C. 0.6879
D. 0.3121
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 2
Find the probability using the standard
normal distribution.
P(z < 1.49)
A. 0.9319
B. 0.0681
C. 0.6879
D. 0.3121
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 3
Find the probability using the standard
normal distribution.
P(z ≥ –2.31)
A. 0.0104
B. 0.0087
C. 0.9896
D. 0.9913
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 4
Find the probability using the standard
normal distribution.
P(z ≥ –2.31)
A. 0.0104
B. 0.0087
C. 0.9896
D. 0.9913
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 5
Find the probability using the standard
normal distribution.
P(–2.14 < z < 0.95)
A. 0.1170
B. 0.0681
C. 0.1873
D. 0.8127
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 6
Find the probability using the standard
normal distribution.
P(–2.14 < z < 0.95)
A. 0.1170
B. 0.0681
C. 0.1873
D. 0.8127
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 7
IQ scores are normally distributed with a
mean of 100 and a standard deviation of
15. Find the probability a randomly
selected person has an IQ score greater
than 120.
A. 0.9082
B. 0.0918
C. 0.6293
D. 0.3707
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 8
IQ scores are normally distributed with a
mean of 100 and a standard deviation of
15. Find the probability a randomly
selected person has an IQ score greater
than 120.
A. 0.9082
B. 0.0918
C. 0.6293
D. 0.3707
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 9
IQ scores are normally distributed with a
mean of 100 and a standard deviation of
15. Find the probability a randomly
selected person has an IQ score between
100 and 120.
A. 0.9082
B. 0.0918
C. 0.4082
D. 0.5918
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 10
IQ scores are normally distributed with a
mean of 100 and a standard deviation of
15. Find the probability a randomly
selected person has an IQ score between
100 and 120.
A. 0.9082
B. 0.0918
C. 0.4082
D. 0.5918
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 11
Find the z-score that has 2.68% of the
distribution’s area to its right.
A. z = 0.9963
B. z = –1.93
C. z = –0.0037
D. z = 1.93
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 12
Find the z-score that has 2.68% of the
distribution’s area to its right.
A. z = 0.9963
B. z = –1.93
C. z = –0.0037
D. z = 1.93
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 13
IQ scores are normally distributed with a
mean of 100 and a standard deviation of
15. What IQ score represents the 98th
percentile?
A. 131
B. 69
C. 113
D. 145
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 14
IQ scores are normally distributed with a
mean of 100 and a standard deviation of
15. What IQ score represents the 98th
percentile?
A. 131
B. 69
C. 113
D. 145
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 15
A population has a mean of 80 and a
standard deviation of 12. Samples of size
36 are selected from the population.
Describe the sampling distribution of x .
A. Normal,  x  80,  x  2
B. Normal,  x  80,  x  12
C. Approximately normal,  x  80,  x  2
D. Approximately normal,  x  80,  x  12
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 16
A population has a mean of 80 and a
standard deviation of 12. Samples of size
36 are selected from the population.
Describe the sampling distribution of x .
A. Normal,  x  80,  x  2
B. Normal,  x  80,  x  12
C. Approximately normal,  x  80,  x  2
D. Approximately normal,  x  80,  x  12
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 17
American children watch an average of 25
hours of television per week with a
standard deviation of 8 hours. A random
sample of 40 children is selected. What is
the probability the mean number of hours
of television they watch per week is less
than 22?
A. 0.3520
B. 0.0089
C. 0.9911
D. 0.6480
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 18
American children watch an average of 25
hours of television per week with a
standard deviation of 8 hours. A random
sample of 40 children is selected. What is
the probability the mean number of hours
of television they watch per week is less
than 22?
A. 0.3520
B. 0.0089
C. 0.9911
D. 0.6480
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 19
Use a correction for continuity to convert
the following interval to a normal
distribution interval.
The probability of getting at least 80
successes
A. x > 80.5
B. x > 79.5
C. x < 80.5
D. x < 79.5
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 20
Use a correction for continuity to convert
the following interval to a normal
distribution interval.
The probability of getting at least 80
successes
A. x > 80.5
B. x > 79.5
C. x < 80.5
D. x < 79.5
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Slide 5- 21