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Chapter 9: Q .8. (page 564)

Stating hypotheses

a. A change is made that should improve student satisfaction with the parking situation at your school. Before the change, 37%of students approve of the parking that's provided. The null hypothesis H0:p∧=0.37H0:p^=0.37is tested against the alternative Ha: p∧>0.37Ha:p^>0.37

b. A researcher suspects that the mean birth weights of babies whose mothers did not see a doctor before delivery is less than 3000 grams. The researcher states the hypotheses as

H0:μ=3000gramsH0:μ=3000grams

Ha:μ≤2999gramsHa:μ≤2999grams

Short Answer

Expert verified

The appropriate hypotheses are:

Part (a)H0:p=0.37,Ha:p>0.37

Part (b)H1:p>0.50,Ha:μ<3000

Step by step solution

01

Part (a)Step 1:Given information

H0:μ=3000gramsH0:μ=3000grams

Ha:μ≤2999gramsHa:μ≤2999grams

02

Part (a) Step 2:Explaination

Inequalities are shown in the null hypothesis not the alternative hypothesis. Here, inequality has been provided in the alternative hypothesis and value of the parameter must be same in both the parameters. So, it is required to replace 2999 by 3000

The hypotheses are:

H0:μ=3000Ha:μ<3000

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Most popular questions from this chapter

Watching grass grow The germination rate of seeds is defined as the proportion of seeds that sprout and grow when properly planted and watered. A certain variety of grass seed usually has a germination rate of 0.80. A company wants to see if spraying the seeds with a chemical that is known to increase germination rates in other species will increase the germination rate of this variety of grass. The company researchers spray a random sample of 400grass seeds with the chemical, and 339of the seeds germinate. Do these data provide convincing evidence at the α=0.05 significance level that the chemical is

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