# Hypothesi testing and confidence interval Q and A

**Tutor description**

5. The IRS claims that it takes 87.3 minutes to prepare a tax form. You believe it takes longer than 87.3 minutes. You survey 25 people and find the following preparation times: 56, 57, 63, 65, 70, 76, 79, 84, 85, 88, 90, 94, 95, 95, 98, 98, 101, 90, 100, 110, 111, 115, 123, 137, 142 Determine if the preparation time is significantly longer than 87.3 minutes. Use α = .025. 6. Given below are the birth weights of babies born to mothers who took special vitamin supplements while pregnant: 3.13 4.37 3.93 4.33 3.39 3.68 4.68 3.52 3.02 4.29 2.47 4.13 4.47 3.22 3.43 2.54 a. Make a 95% confidence interval for the mean weight of babies whose mothers take vitamin supplements. b. Do a hypothesis test to determine if these babies weight is more than the mean weight for the population of all babies which is 3.39 kg using α = .025 c. In a short paragraph, describe the relationship between your answer to part (a) and your answer to part (b). 7. A

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