Previously, an organization reported that teenagers spent 4.5
hours per week, on average, on the phone. The organization thinks
that, currently, the mean is higher. Fifteen randomly chosen
teenagers were asked how many hours per week they spend on the
phone. The sample mean was 4.75 hours with a sample standard
deviation of 2.0. Conduct a hypothesis test, the Type I error
is:
a.to conclude that the current mean hours per week is higher
than 4.5, when in fact, it is higher
b.to conclude that the current mean hours per week is higher
than 4.5, when in fact, it is the same
c.to conclude that the mean hours per week currently is 4.5,
when in fact, it is higher
d.to conclude that the mean hours per week currently is no
higher than 4.5, when in fact, it is not higher