Normal distribution
Empirical rule practice
1. For the distribution N(155, 9), use the empirical rule (68-95-99.7 rule) to determine the percent of data values between 138 and 155.
Practice Area under the curve.
2. What is the percentage of a normal distribution that is less than the mean?
Normal Distribution Practice Problems
3. For a normal model with mean 9.7 and a standard deviation of 1.2, what proportion of data values are greater than 10?
4. The age of student in a community college is normally distributed with a mean of 30 years and standard deviation σ = 4 years. Let X represent the age of a randomly selected student. Find a) P(x < 40) b) P(x > 21) c) P(30 < x < 35)
5. Entry to a certain University is determined by a national test. The scores on this test are normally distributed with a mean of 500 and a standard deviation of 100. Tom wants to be admitted to this university and he knows that he must score better than at least 70% of the students who took the test. Tom takes the test and scores 585. Will he be admitted to this university?