# Probability & Stats - Normal Distrabutions

*label*Statistics

*timer*Asked: Mar 2nd, 2015

**Question description**

1) The lengths in minutes of feature films for the current year follow a normal distribution with a mean of 109 minutes and a standard deviation of 12 minutes. What percentage of feature films in the current year last longer than two hours (120 minutes)?

2) The scores on a particular test are normally distributed with mean of 73 and standard deviation 5. What score would a student need to be among the top 10% of all test scores?

3) Explain when the Central Limit Theorem needs to be used to answer a normal probability question. Is the case of n = 1 included in the Central Limit Theorem?