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9. Facebook Friends: Based on a study of U.S. Facebook users in 2014, the most connected age group were Facebook users between 18 and 24 years, averaging 649 friends on the social media website. Assume the distribution for the number of Facebook friends for this age group is approximately normal with mean of 649 friends and a standard deviation of 150 friends. a. Based on the model, determine the value that would correctly complete the sentence below. 
Using the z table we find that a z score = 1.04 has an area to the left of 0.8500. So we need to solve for the number of friends: 𝟏𝟏 . 𝟎𝟎𝟒𝟒 = 𝒙𝒙−𝟔𝟔𝟒𝟒𝟔𝟔 𝟏𝟏𝟓𝟓𝟎𝟎 , x = 649 + 1.04(150) = 802 Note: If they use z = 1.05 and get 803.5 it is ok. Final Answer: at least ______ 802 ______ friends b. Based on the model, what is the probability that a randomly selected Facebook user between 18 to 24 years has at least 844 friends? 
c. Consider a random sample of 8 Facebook users between 18 to 24 years. What is the probability that exactly 3 of the 8 Facebook users will have at least 844 friends? 
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