The following table shows the results of a survey of 200 authors by a publishing company. New Authors Established Authors Total 12 48 60 34 106 140 Total 46 154 200 Compute the relative frequency of the given event if an author as specified is chosen at random. An author is a new author. Successful Unsuccessful

Race organizers want to survey the participating runners on the quality of the running course. Which of the following uses systematic random sampling? Select the first 15 finishers and the last 15 finishers to take the survey. Randomly select 15% of the male participants and 15% of the female participants. Select the 5th finisher (with the number 5 being randomly chosen) to survey, then survey every 15th finisher after that. Sort all of the runners' names alphabetically, then randomly choose 2 letters and survey all participants whose last name begins with one of those letters.

A 2012 study of freely forming groups in bars all over Europe examined the natural behavior of groups. The researchers recorded the group size (number of individuals in the group) of all 501 groups in the study that were naturally laughing. The findings were displayed in the figure below. 300 Number of groups 250 200 O 52 O 2.7 0 2 150 3.5 4 100 50 0 254 2 Enter your answer here The median laughter group size in this study is 168 3 The mean laughter group size in this study is O 100.2 Enter your answer here 52 4 5 Laughter group size 21 6 6 Can we conclude from these findings that, in European bars in 2012, smaller groups were more likely than larger groups to be naturally laughing? Explain your statistical reasoning in one sentence.

As part of a statistics project, a teacher brings a bag of marbles containing 700 white marbles and 300 red marbles. She asks her students to determine how many red marbles are in the bag without counting them.A student randomly draws 100 marbles from the bag. Of the 100 marbles, 33 are red.The target population consists of The 100 marbles drawn by the student The 1000 marbles in the bag None of the above The 33 red marbles drawn by the student The 300 red marbles in the bag The sample consists of The 1000 marbles in the bag The 100 marbles drawn by the student The 33 red marbles drawn by the student None of the above The 300 red marbles in the bag Based on the sample, the student would estimate that ------   marbles in the bag were red.

A sports franchise knows that 81% of their season ticket holders attend every home game.  The collect a random sample of size 250 from among last year's season ticket holders.  How likely are they to find that 200 or fewer attended every home game?   a. .657   b. .800   c. .343   d. .500

Suppose that 20% of fruit flies possess a certain gene.  If we randomly select 20 fruit flies, find the probability that at least 5 flies in the sample possess the gene.  You may assume sampling with replacement. Group of answer choices

A national park is famous for its beautiful desert landscape and its many natural rock formations. The following table is based on information gathered by a park ranger of all rock formations of at least 3 feet. The height of the rock formation is rounded to the nearest foot. Height of rock formation, feet 3–9 10–29 30–49 50–74 75 and higher Number of rock formations in park 115 90 21 26 18 For a rock formation chosen at random from this park, use the preceding information to estimate the probability that the height of the rock formation is as follows. (Round your answers to two decimal places.) (a) 3 to 9 feet(b) 30 feet or taller(c) 3 to 49 feet(d) 10 to 74 feet(e) 75 feet or taller

A manufacturing plant knows that in reality 80% of products made are perfect. An inspector selects four products at random. What is the mean number of perfect products in any sample of 4? It can be assumed that each product is independent of the others.

Fortune publishes data on sales, profits, assets, stockholders' equity, market value, and earnings per share for the 500 largest U.S. industrial corporations every year. Assume that you want to select a simple random sample of 10 corporations from the Fortune 500 list. Use the last three digits in column 10 of the table of random numbers, beginning with 945. Read down the column and identify the numbers of the 10 corporations that would be selected. (Enter your answers as a comma-separated list.)

A store manager gathers some demographic information from the store's customers. The following chart summarizes the age-related information they collected: