Question

The accompanying data table ists measured voltlage amounts supplied drectly to a famly's home The power supply company sthat it has a target power supply of 120 volts Using those hone votage amouns. test the dlaim that the men s 120 vols ea Click the icon to viewr the sample data Click the icon to view a table of oritical tvales What are the n and atemative hypotheses? o120 Caloulate the test statsic (Round to three deimal pleces as nended) What is thenge of vakues for the Pvae Cheose the conet answer below dentty the critical vales) Rsund to three decimal places as needed Use a comma to separate answers as needed Click to select your answens)

Answer 1

Solution:-

State the hypotheses. The first step is to state the null hypothesis and an alternative hypothesis.

Null hypothesis: u = 120
Alternative hypothesis: u $\neq$ 120

Note that these hypotheses constitute a two-tailed test.

Formulate an analysis plan. For this analysis, the significance level is 0.05. The test method is a one-sample t-test.

Analyze sample data. Using sample data, we compute the standard error (SE), degrees of freedom (DF), and the t statistic test statistic (t).

SE = s / sqrt(n)

S.E = 0.04385

DF = n - 1

D.F = 39
t = (x - u) / SE

t = - 85.0

t_critical = + 2.023

where s is the standard deviation of the sample, x is the sample mean, u is the hypothesized population mean, and n is the sample size.

Since we have a two-tailed test, the P-value is the probability that the t statistic having 49 degrees of freedom is less than - 85.0 or greater than 85.0.

Thus, the P-value = less than 0.0001.

(D) P-value < 0.01

Interpret results. Since the P-value (almost 0) is less than the significance level (0.05), we have to reject the null hypothesis.