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Chapter 10: Q. 16 (page 623)

A study by the National Athletic Trainers Association surveyed random samples of 1679high school freshmen and 1366high school seniors in Illinois. Results showed that 34of the freshmen and 24 of the seniors had used anabolic steroids. Steroids, which are dangerous, are sometimes used to improve athletic performance. Is there a significant difference between the population proportions? State appropriate hypotheses for a significance test to answer this question. Define any parameters you use.

Short Answer

Expert verified

H0:p1-p2=0

Ha:p1-p2鈮�0

Step by step solution

01

Given Information

Given

x1=34

n1=1679

x1=24

n2=1366

02

Explanation

The null hypothesis states that the population proportions are equal or that their difference is zero:

H0:p1-p2=0

The alternative hypothesis states the opposite of the null hypothesis (according to the claim):

Ha:p1-p2鈮�0

p1is the population proportion of freshmen that used anabolic steroids.

p2is the population proportion of seniors that used anabolic steroids.

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