problem: customers are complaining about the sandwich length Interpret the results: **please just interpret the last three** You are the owner of three local sandwich shops. Recently you've received complaints fromcustomers that their "footlong" sub sandwiches were less than 12 inches long. As a measure ofquality assurance, data was collected on all footlong sub sandwiches made over the period of anhour at each store. Determined which, if any, of your stores are making sub sandwiches that aresignificantly shorter than 12 inches. You will conduct three t-tests, one for each store. You want tobe 95% confident in your results. (Note. This case is inspired by reality. Search the internet for'claims over footlong sub' for a historical perspective and how a company used statistics to insureconsistent quality.)Sandwich MeasurementsStatisticsStore 1Store 2Store 3Store 1Store 2Store 3Sample SizeMean (length)Variance8.89.19.0188.11.411.612.511.0011.0012.1013.413.415.12.312.2511,311.414.3Standard Deviation1.521.502.1810.110.310.812.4Hypothesized Mean (M)Difference in Means (x - M)12,413.812121210.410.611.2|-1.00-1.000.108.99.29.1Standard Error0.360.530.4910.411.1T-Statistic-2.79-1.890.2111.814.0Degrees of Freedom12.814.39.38.7P-value P(T=t) two-tail*5012.613.7*Remember that the T.DIST.2T() function requires the t-statistic11.7argument to be an absolute value, not a negative value, or an error12.9711.8will occur.13.089.710.2-912.614.18.68.6Interpret the Results1. What is the null hypothesis for these tests?2. What is the alternative hypothesis for these tests?3. Given the desired confidence level, what alpha should be used?3114.6HO: µ = 12H1: u123211.03334354. Can you say with 95% confidence that Store 1 is producing subsandwiches with an average length that is less than 12 inches?5. Can you say with 95% confidence that Store 2 is producing subsandwiches with an average length that is less than 12 inches?6. Can you say with 95% confidence that Store 3 is producing subsandwiches with an average length that is less than 12 inches?a=0.05[select]3637[select]3839[select)404142434445

The data shows the sandwich measurements for three stores.

alpha should be used? 4. Can you say with 95% confidence that Store 1 is producing sub sandwiches with an average length that is less than 12 inches? 5. Can you say with 95% confidence that Store 2 is producing sub sandwiches with an average length that is less than 12 inches? 6. Can you say with 95% confidence that Store 3 is producíng sub sandwiches with an average length that is less than 12 inches? a =0.05 [select] [select] [select]

alpha should be used? 4. Can you say with 95% confidence that Store 1 is producing sub sandwiches with an average length that is less than 12 inches? 5. Can you say with 95% confidence that Store 2 is producing sub sandwiches with an average length that is less than 12 inches? 6. Can you say with 95% confidence that Store 3 is producíng sub sandwiches with an average length that is less than 12 inches? a =0.05 [select] [select] [select]

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter10: Statistics

Section10.3: Measures Of Spread

Problem 1GP

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