Preliminary data analyses and other information suggest that you can reasonably assume that the variables under consideration in Exercises 11.21–11.26 are
11.24 Premade Pizza. Homestyle Pizza of Camp Verde, Arizona, provides baking instructions for its premade pizzas. According to the instructions, the average baking time is 12 to 18 minutes. If the times are normally distributed, the standard deviation of the times should be approximately 1 minute. A random sample of 15 pizzas yielded the following baking times to the nearest tenth of a minute.
At the 1% significance level, do the data provide sufficient evidence to conclude that the standard deviation of baking times exceeds 1 minute? (Note: The sample standard deviation of the 15 baking limes is 1.54 minutes.)
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Introductory Statistics (10th Edition)
- "In your response indicate whether CPAs in states that have flat state income tax rates work fewer hours per week during tax season compared to the US average. You will want to formally set up H0 and Ha, report either the test statistic (z-value) or p-value, and explain why you either reject or fail to reject your null hypothesis."arrow_forwardA biologist was interested in determining whether specific seedlings treated with a new fertilizer resulted in a higher than average height than the standard height of 11.2 cm. The biologist treated a random sample of 24 seedlings with the fertilizer and subsequently obtained the following heights. Conduct an appropriate hypothesis test using a 5% significance level. What is the null and alternative hypothesis? What is the value of the test stastic? Please show work. 11.5 11.8 15.7 12.1 10.1 10.5 16.5 13.5 14.4 16.7 10.9 10.0 11.1 17.1 13.3 12.4 8.5 14.3 12.9 11.1 15.0 13.3 9.9 13.5arrow_forwardUse the data below to test the claim that the weight loss was greater with the low fat diet compared to the low carbohydrate diet. Use a 5% level of significance. Low Fat Low Carbohydrate x¯1=4.7lbs1=7.2lbn1=77 x¯1=3.5lbs1=6.9lbn1=52 Identify the tail of the test. What is the P-value? Will the null hypothesis be rejected? Is the initial claim supported?arrow_forward
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