Question 596030
The test statistic found <a href="http://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.596028.html">here</a> was z = -8.85437744847147 (approximately)


This is very very far from the center value of z = 0. In fact, it's more than 8 standard deviations away from the mean. So it's <u>very</u> unlikely to observe this value if it randomly came up (assuming the null is true). Usually, the most likely values will fall within 3 standard deviations (on either side). But this is more than 8 standard deviations away.


This means that the p-value is <u>very</u> small. So small that it's practically zero. Since the p-value is less than the significance level of 0.05, we reject the null hypothesis.


So we can conclude that college students watch fewer DVDs a month than high school students.