Currently patrons at the library speak at an average of 66 decibels. Will this average increase after the installation of a new computer plug in station? After the plug in station was built, the librarian randomly recorded 69 people speaking at the library. Their average decibel level was 67.7 and their standard deviation was 13. What can be concluded at the the αα = 0.10 level of significance? For this study, we should use Select an answer z-test for a population proportion t-test for a population mean  The null and alternative hypotheses would be:       H0:H0:  ? μ p  Select an answer ≠ = < >         H1:H1:  ? p μ  Select an answer < ≠ = >     The test statistic ? z t  =  (please show your answer to 3 decimal places.) The p-value =  (Please show your answer to 4 decimal places.) The p-value is ? > ≤  αα Based on this, we should Select an answer fail to reject accept reject  the null hypothesis. Thus, the final conclusion is that ... The data suggest the populaton mean has significantly increased from 66 at αα = 0.10, so there is statistically significant evidence to conclude that the population mean decibel level at the library has increased since the plug in station was built. The data suggest the population mean has not significantly increased from 66 at αα = 0.10, so there is statistically significant evidence to conclude that the population mean decibel level at the library has not increased since the plug in station was built. The data suggest that the population mean decibal level has not significantly increased from 66 at αα = 0.10, so there is statistically insignificant evidence to conclude that the population mean decibel level at the library has increased since the plug in station was built.

Currently patrons at the library speak at an average of 66 decibels. Will this average increase after the installation of a new computer plug in station? After the plug in station was built, the librarian randomly recorded 69 people speaking at the library. Their average decibel level was 67.7 and their standard deviation was 13. What can be concluded at the the αα = 0.10 level of significance?

1. For this study, we should use Select an answer z-test for a population proportion t-test for a population mean 
2. The null and alternative hypotheses would be:     

 H0:H0:  ? μ p  Select an answer ≠ = < >       

 H1:H1:  ? p μ  Select an answer < ≠ = >    

1. The test statistic ? z t  =  (please show your answer to 3 decimal places.)
2. The p-value =  (Please show your answer to 4 decimal places.)
3. The p-value is ? > ≤  αα
4. Based on this, we should Select an answer fail to reject accept reject  the null hypothesis.
5. Thus, the final conclusion is that ...
   • The data suggest the populaton mean has significantly increased from 66 at αα = 0.10, so there is statistically significant evidence to conclude that the population mean decibel level at the library has increased since the plug in station was built.
   • The data suggest the population mean has not significantly increased from 66 at αα = 0.10, so there is statistically significant evidence to conclude that the population mean decibel level at the library has not increased since the plug in station was built.
   • The data suggest that the population mean decibal level has not significantly increased from 66 at αα = 0.10, so there is statistically insignificant evidence to conclude that the population mean decibel level at the library has increased since the plug in station was built.