Answer:
Based on the claim (the average loss is 20 pounds) the system of hypothesis for this case are:
Null hypothesis [tex]\mu = 20[/tex]
Alternative hypothesis: [tex] \mu \neq 20[/tex]
Step-by-step explanation:
For thi case we want to test if the "fat-burner" pill present and average loss of 20 pounds in the first month.
And in order to test this hypothesis they have the following sample data:
[tex]n = 100[/tex] represent the sample size
[tex]\bar X = 18[/tex] the sample average fro the lost weight
[tex]s = 7.5[/tex]
Based on the claim (the average loss is 20 pounds) the system of hypothesis for this case are:
Null hypothesis [tex]\mu = 20[/tex]
Alternative hypothesis: [tex] \mu \neq 20[/tex]
And in order to test the hypothesis we can use the following statistic:
[tex] t = \frac{\bar X -\mu}{\frac{s}{\sqrt{n}}}[/tex]