Part 1. Demonstrate that you understand basic concept of Normal Distribution. In
ID: 3158911 • Letter: P
Question
Part 1. Demonstrate that you understand basic concept of Normal Distribution. In two small paragraphs describe a couple of properties/rules of Normal distribution. Hint: look for KEY FACTS and DEFINITIONS in sections 6.1 and 6.2 of the eText. Give one example of some practical case where we can use Normal distribution (like the example I gave of IQ scores.)
Part 2. Assign your numbers for mean and standard deviation . Make sure is about four times bigger than . Then select any number "a" below or above mean , but not too far from , difference (a - ) should be less than 3. For example, = 80, = 20, a = 90 (or a = 75). Find following two probabilities: 1) P(x < a) 2) P(x > a) First, use formula: z = (a - )/ to calculate z-value and then use Appendix Table for Standard Normal Distribution. Remember, Appendix Table gives you probability P(xa) use formula: P(x>a) = 1 - P(x
Explanation / Answer
For example, = 80, = 20, a = 90
P( z < 90- 80 / 20 )
P( z < 0.5 ) = 1 - 0.3085 = 0.6915
P( z > 90 - 80 / 20 )
P( z> 0.5) = 0.3085