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The Practice of Statistics Fourth Edition Chapter 2 2.1 Describing Location in a Distribution
The Practice of StatisticsFourth Edition
Chapter 22.1 Describing Location in a Distribution
Onemorestepinthestrategy:4.Sometimestheoverallpatternofalargenumberofobservationsissoregularthatwecandescribeitasmoothcurve.
The mean and the median of a symmetric density curve are equal.
Problem 28, page 108 Uniform Distribution
Problems 31,32, page 108
2.2 Normal Distributions: are described by normal curves ( symmetric, unimodal, bell-shaped)
The points at which this change of curvature takes place are located at distanceσ on either side of the mean μ.
The Normal Curve Applet!!!
www.whfreeman.com/tps4e
Find the rule!
1.28 NCAA partial qualifiers. The NCAA considers a student a “partialqualifier” eligible to practice and receive an athletic scholarship, but not tocompete, if the combined SAT score is at least 720. What proportion of allstudents who take the SAT would be partial qualifiers? That is, what proportionhave scores between 720 and 820?
area between720 and 820= area left of 820 − area left of 7200.0905 = 0.1621 − 0.0716About 9% of all students who take the SAT have scores between 720 and 820
Normal curve applet!
