Question 1184016

{{{H[0]:  mu = 5}}}
{{{H[a]:  mu > 5}}}

Use a one-tailed z-test since it is known prior that underlying population is normally distributed with a known standard deviation of {{{sigma = 1.5}}}.

===> {{{z = ((X-bar) - mu)/(sigma/sqrt(n)) =  (6 - 5)/(1.5/sqrt(10)) = 2.108}}}


===> p-value = 0.018 < 0.05 = {{{alpha}}}.


Hence, reject the null hypothesis and conclude that the number of essays per week may have already increased from 5.