Download Exam 1 Problems | Introduction to Statistics | STAT 1222 and more Exams Statistics in PDF only on Docsity! Statistics 1222, Section 700 Exam 1 Due Thursday, February 11th no later than midnight Problem 1 (worth 10 points) A sample of eight resistors of a certain type resulted in the following sample resistances (ohms) 40, 43, 39, 35, 37, 43, 46, 37 Find the median of the sample a)36 b)37.5 c) 39.5 d) 38.5 e)43 Problem 2 (worth 10 points) Based on the problem 1 above Find the first quartile of the sample a) 35 b)39 c)43 d) 37 e)40 Problem 3(worth 10 points) In a survey of 250 juniors majoring in psychology or communications at a large university, the students were asked whether or not they are happy with their majors. The following table gives the result of the survey. Assume that none of these students from this group majors in both areas. Happy Unhappy Total Psychology 80 20 Communications 115 35 What is the probability that a randomly selected student from this group is happy with his choice of the major a) 0.16 b)0.25 c)0.32 d)0.84 e) 0.78 Problem 4(worth 10 points) Based on the problem 2 above What is the probability that a randomly selected student from this group is unhappy with the choice of major or is a communications major? a) 0.82 b)0.59 c)0.68 d)0.84 e)0.23 Problem 5(worth 10 points) The recommended prices (in dollars) for several stocks that analysts predict should produce at least 10% annual returns are: 41 20 22 14 15 25 18 40 17 14 Find the mean, median, and mode of the data, if possible. If it is not possible, explain why the measure of central tendency cannot be found Problem 6 (worth 10 points) Sample SAT scores for eight males and eight females are listed: Male SAT scores: 1059 1328 1175 1123 923 1017 1214 1042 Female SAT scores: 1226 965 841 1053 1056 1393 1312 1222 a)Find the range, variance, and standard deviation of each data set b)Interpret the results in the context of the real-life setting Problem 7 (worth 10 points) Three adult males in the 20-29 age group are randomly selected. Their heights are 74 inches, 62 inches, and 80 inches. Use z-scores to determine which heights, if any, are unusual, given that heights of males in the United states in that age group have a bell- shaped distribution with a mean of 69.2 inches and a standard deviation of 2.9 inches.
