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HW 4 , TMTH 3.360% (27927]. . X + G C O i webassignnet @ Raymond Noe, Ray... at Human Resource M... 9 Human Ecosystems... (5 Maria ngHiiman... E] inclusion Preview le... 23. [DB Points] PREVIOUS ANSWERS MENDSTAT14 415.096. MY NOTES l | ASK YOUR TEACHER l | PRACTICE ANOTHER l The maximum patent life for a new drug is 17 years. Subtracting the length oftime required by the FDA for testing and approval of the drug provides the actual patent life ofthe drugithat is, the length of time that a company has to recover research and development costs and make a prot. Suppose the distribution of the lengths of patent life for new drugs is as shown here. Vears, x' 3 4 5 6 7 8 9 10 11 12 13 p(x) '0.03 0.05 0.07 0.10 0.14 0.21 0.17 0.12 0.07 0.03 0.01 (a) Find the expected number of years of patent life for a new drug. x (b) Find the standard deviation ofx. (Round your answer to four decimal places.) 3.1623 x (c) Find the probability that x falls into the interval y i 20. x 24. [1I1 Paints] PREVIOUS ANSWERS MENDSTAT14 415.104. ASK YOUR TEACHER A retailer sells two styles of highapriced digital Video recorders (DVR) that experience indicates are in equal demand. (Fifty percent of all potential customers prefer style 1, and 50% favor style 2.) 1f the retailer stocks four of each, what is the probability that the first four customers seeking a DVR all purchase the same style? (Enter your probability as a fraction.)