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Steroids in high school A study by the National Athletic Trainers Association surveyed random samples of 1679high school freshmen and 1366 high school seniors in Illinois. Results showed that 34of the freshmen and 24of the seniors had used anabolic steroids. Steroids, which are dangerous, are sometimes used in an attempt to improve athletic performance. Researchers want to know if there is a difference in the proportion of all Illinois high school freshmen and seniors who have used anabolic steroids.

a. State appropriate hypotheses for performing a significance test. Be sure to define the parameters of interest.

b. Check if the conditions for performing the test are met.

Short Answer

Expert verified

a. The hypothesis are: H0:p1=p2and Ha:p1p2

b. All conditions are met.

Step by step solution

01

Given Information

It is given that researchers want to know if there is difference in proportion of all Illinois high school and seniors using steroids or not.

x1=34

x2=24

n1=1679

n2=1366

02

Hypothesis for performing significance test

Claim is difference between the proportions.

Appropriate hypothesis are:

Null: H0:p1=p2

Alternative hypothesis: Ha:p1p2

p1isrole="math" localid="1654706370645" proportionfreshmen in Illinois that used anabolic steroids.

p2isproportion ofseniors in Illinois that used anabolic steroids.

03

Checking the conditions

Conditions are:

Random: Samples are independent random samples from separate populations.

Independent: 1679<10%of high school freshmen and 1366<10%of high school seniors.

Normal: There are 34success and 1679-34=1645failures in first sample and 24success and 1366-24=1342failures in second sample, all are less than ten.

All conditions are satisfied, we can use hypothesis test.

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