CK-12 Probability and Statistics - Advanced

http://www.ck12.org Chapter 5. Normal Distribution

3. about 0.15% (more than 3 standard deviations above the mean)


4. The standard normal curve has a mean of zero and a standard deviation of one, so all the values correspond to
   z−scores. The corresponding values are approximately:

1. 0. 84

2. 0. 16

3. 0

4. 1

5. 0. 025

Therefore the correct order is: c, e, b, a, d

4. c


5. 
   
   
   
   0. 
      
      
      
      25. 157 .7 is exactly 2 standard deviations above the mean height. According to the empirical rule, the
          probability of a randomly chosen value being within 2 standard deviations is about 0.95, which leaves 0. 05
          in the tails. We are interested in the upper tail only as we are looking for the probability of being above this
          value.
      
      
      
      
   
   
   
   


6. (a) Here are the possible plots showing a symmetric, mound shaped distribution.