The null hypothesis is a statement with describe the claim of 'no difference'.
Let [tex]\mu[/tex] be the population mean.
Given claim : The mean age of bus drivers in Chicago is 50.3 years.
i.e. [tex]\mu=50.3[/tex]
Since the null hypothesis takes the statement having equal sign or " no difference with mean".
Then, the null hypothesis for the given situation is
[tex]H_0:\mu=50.3[/tex]
If the test fails to reject the null hypothesis, it means there is evidence to support the claim that the the mean age of bus drivers in Chicago is 50.3 years.
