This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: c Kendra Kilmer October 27, 2011 Section 8.2  Expected Value Example 1 : Records kept by the chief dietitian at the university caferteria over a 25wk period show the following weekly consumption of milk (in gallons): Milk 200 201 202 203 204 Weeks 4 6 8 5 2 Find the average number of gallons of milk consumed per week in the cafeteria. Definition : Let X denote a random variable that assumes the values x 1 , x 2 ,..., x n , with associated probabilites p 1 , p 2 ,..., p n , respectively. Then the expected value of X , E ( X ) , is given by: E ( X ) = x 1 p 1 + x 2 p 2 + x n p n Example 2: Referring to Example 1, let the random variable X denote the number of gallons of milk consumed in a week at the cafeteria. a) Find the probability distribution of X . b) Compute E ( X ) c) Draw a histogram for the random variable X Note : If we think of placing the histogram on a seesaw, the expected value occurs where we would put the fulcrum to balance it....
View
Full
Document
 Fall '08
 JillZarestky

Click to edit the document details