Can someone point me in the right direction with this Statistics problem? Any help at all is appreciated!?

[Richarddddddd]

Research indicates that college students spend on average 4 hours on Facebook every
day. A random sample of 100 college students in Connecticut indicates that students
spend 3.5 hours on Facebook with a standard deviation of 2. Test the hypothesis that
college students in Connecticut spend less time on Facebook than the national average
(critical value is 1.645 when df ≥ 100).

[Charles D]

Ho: mu >=4
Ha: mu < 4 (claim)

x-bar = 3.5
s = 2
n = 100

test statisitc z = (x-mu)/ (s/sqrtn)) = ( 3.5 - 4 ) / (2 / sqrt(100) ) = -0.5 / 0.2 = - 2.5

The the null hypothesis has a <, the critical value is -1.645. The test statistic is well into the rejection region. So we reject Ho and there is sufficient evidence to accept the claim.

(See also "Khan Academy Hypothesis Testing")