The ages of students in a middle school have the following probability distribution: x 12 13 14 15 P(x) 0.25 0.29 0.32 0.14 a) What is the probability a student chosen at random is no less than 13 years old? b) What is the mean age of the students in middle school? c) What is the standard deviation for the ages of the students in the middle school?

A recent survey reported that 38% of 18- to 29-year-olds in a certain country own tablets. Using the binomial distribution, complete parts (a) through (e) below. a. What is the probability that in the next six 18- to 29-year-olds surveyed, four will own a tablet? The probability is (Type an integer or a decimal. Round to four decimal places as needed.) b. What is the probability that in the next six 18- to 29-year-olds surveyed, all six will own a tablet? The probability is (Type an integer or a decimal. Round to four decimal places as needed.) c. What is the probability that in the next six 18- to 29-year-olds surveyed, at least four will own a tablet? The probability is (Type an integer or a decimal. Round to four decimal places as needed.) d. What are the mean and standard deviation of the number of 18- to 29-year-olds who will own a tablet in a survey of six? The mean number of 18- to 29-year-olds who own tablets out of six surveyed is. (Type an integer or a decimal. Round to four…

81. According to a recent Pew Research poll, 75% of millennials (people born between 1981 and 1995) have a profile on a social networking site. Let X = the number of millennials you ask until you find a person without a profile on a social networking site. a. Describe the distribution of X. b. Find the (i) mean and (ii) standard deviation of X. c. What is the probability that you must ask ten people to find one person without a social networking site? d. What is the probability that you must ask 20 people to find one person without a social networking site? e. What is the probability that you must ask at most five people?