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Pearson eText for Essentials of Statistics -- Instant Access (Pearson+)
6th Edition
ISBN: 9780137517374
Author: Mario Triola
Publisher: PEARSON+
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Textbook Question
Chapter 6.2, Problem 35BB
Curving Test Scores A professor gives a test and the scores are
a. If she curves by adding 15 to each grade, what is the new mean and standard deviation?
b. Is it fair to curve by adding 15 to each grade? Why or why not?
c. If the grades are curved so that grades of B are given to scores above the bottom 70% and below the top 10%, find the numerical limits for a grade of B.
d. Which method of curving the grades is fairer: adding 15 to each original score or using a scheme like the one given in part (c)? Explain.
Expert Solution & Answer
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Chapter 6 Solutions
Pearson eText for Essentials of Statistics -- Instant Access (Pearson+)
Ch. 6.1 - Normal Distribution Whats wrong with the following...Ch. 6.1 - Normal Distribution A normal distribution is...Ch. 6.1 - Standard Normal Distribution Identify the two...Ch. 6.1 - Notation What does the notation z indicate?Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Continuous Uniform Distribution. In Exercises 58,...Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...
Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...Ch. 6.1 - Standard Normal Distribution. In Exercises 912,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1316,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Standard Normal Distribution. In Exercises 1736,...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Finding Bone Density Scores. In Exercises 3740...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Critical Values. In Exercises 4144, find the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Basis for the Range Rule of Thumb and the...Ch. 6.1 - Significance For bone density scores that are...Ch. 6.1 - Distributions In a continuous uniform...Ch. 6.2 - Birth Weights Based on Data Set 4 Births in...Ch. 6.2 - Birth Weights Based on Data Set 4 Births in...Ch. 6.2 - Normal Distributions What is the difference...Ch. 6.2 - Random Digits Computers are commonly used to...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 58, find the area of the...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - IQ Scores. In Exercises 912, find the indicated IQ...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - Seat Designs. In Exercises 1320, use the data in...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - In Exercises 2124, use these parameters (based on...Ch. 6.2 - Eye Contact In a study of facial behavior, people...Ch. 6.2 - Designing a Work Station A common design...Ch. 6.2 - Jet Ejection Seats The U.S. Air Force once used...Ch. 6.2 - Quarters After 1964, quarters were manufactured so...Ch. 6.2 - Low Birth Weight The University of Maryland...Ch. 6.2 - Body Temperatures Based on the sample results in...Ch. 6.2 - Durations of Pregnancies The lengths of...Ch. 6.2 - Water Taxi Safety When a water taxi sank in...Ch. 6.2 - Curving Test Scores A professor gives a test and...Ch. 6.2 - Outliers For the purposes of constructing modified...Ch. 6.3 - Births There are about 11,000 births each day in...Ch. 6.3 - Sampling with Replacement The Orangetown Medical...Ch. 6.3 - Unbiased Estimators Data Set 4 Births in Appendix...Ch. 6.3 - Sampling Distribution Data Set 4 Births in...Ch. 6.3 - Good Sample? 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In Exercises...Ch. 6.5 - Prob. 9BSCCh. 6.5 - Constructing Normal Quantile Plots. In Exercises...Ch. 6.5 - Prob. 18BSCCh. 6.5 - Constructing Normal Quantile Plots. In Exercises...Ch. 6.5 - Constructing Normal Quantile Plots. In Exercises...Ch. 6.5 - Transformations The heights (in inches) of men...Ch. 6.5 - Lognormal Distribution The following are the...Ch. 6.6 - Continuity Correction In testing the assumption...Ch. 6.6 - Checking Requirements Common tests such as the...Ch. 6.6 - Notation Common tests such as the SAT, ACT, LSAT,...Ch. 6.6 - Distribution of Proportions Each week, Nielsen...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Using Normal Approximation. In Exercises 58, do...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Car Colors. In Exercises 912, assume that 100 cars...Ch. 6.6 - Tennis Replay In the year that this exercise was...Ch. 6.6 - Tennis Replay Repeat the preceding exercise after...Ch. 6.6 - Smartphones Based on an LG smartphone survey,...Ch. 6.6 - Eye Color Based on a study by Dr. P. Sorita at...Ch. 6.6 - Mendelian Genetics When Mendel conducted his...Ch. 6.6 - Sleepwalking Assume that 29.2% of people have...Ch. 6.6 - Voters Lying? In a survey of 1002 people, 701 said...Ch. 6.6 - Cell Phones and Brain Cancer In a study of 420,095...Ch. 6.6 - Births The probability of a baby being born a boy...Ch. 6.6 - Overbooking a Boeing 767-300 A Boeing 767-300...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Bone Density Test. In Exercises 14, assume that...Ch. 6 - Notation a. 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