Statistic Homework Page 240 Problem #23 In Gallup's Annual Consumption Habits Poll, telephone interviews were conducted for q random sample of 1014 adults aged 18 and over. One of the questions was, \"How many cups of coffee, if any, do you drink on an average, day?\" The following table shows the results obtained (Gallup website, August 6, 2016 Number of cups per Day Number of Responses 0 1 2 3 365 264 193 91 4 or more 101 Define a random variable X= number of cups of coffee consumed on an average day. Let X=4 represent four or more cups. a. b. c. d. Develop a probability distributions for X Compute the expected value for X. Compute the variance for X Suppose we are only interested in adults who drink at least one cup of coffee on an average day. For this group, let Y = the number of cups of coffee consumed on an average day. Compute the expected values of Y and compare it to the expected value of X. Page 287 Problem #17 The mean cost of domestic airfares in the United States rose all-time high $385 per ticket (Bureau of Transportation Statistics website, November/ 2, 2012). Airfares were based on on the total ticket value, which consider of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with standard deviation of $110 a. What is the probability that a domestic airfare is $550 or more? b. What is the probability that a domestic airfare is $250 or less? c. What is the probability that a domestic airfare is between $300 and $500? d. What is the cost for the 3% highest domestic airfares