Additional Attachment

Math 21 Online - Practice Final Answer Key • For sample size problems, just state the appropriate sample size. • For confidence interval problems, express your answer in a sentence. • For hypothesis tests, use the standard 5-step procedure.

1. Ho & Hl 2. alpha 3. test 4. test statistic & p-value 5. Decision about Ho and conclusion

1) A news agency is planning a poll. The agency wants to determine w� American citizens supported NATO involvement in Kosovo. If the agency wants to be 95% sure that the sample proportion differs from the true population proportion by no more than 4%, how large of a sample is necessary? ---

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G-""'tle s;te_ : (of l 2) A high school counselor wants to estimate the �mbined score for high school students. He has been told that the standard deviation for all such scores 1s approximately 230 points. How large of a sample is required in order to be 99% sure that his sample mean is off by no morelnan 10 points from the true mean SAT combined score. £ f:. ?, - s� t>

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11} To test the belief that sons are taller than their fathers, a student randomly selects 13 fathers who

have adult male children. She records the height of both the father and son in inches and obtains the

following data. Test the claim that sons are taller than their fathers at the 0.05 level of significance.

Family 1 2 3 4 5 6 7 8 9 10 11

Father 70.3 67.1 70.9 66.8 72.8 70.4 71.8 70.1 69.9 70.8 70.2

Son 74.1 69.2 66.9 69.2 68.9 70.2 70.4 69.3 75.8 72.3 69.2

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70.4 72.4

68.6 73.9