You look at real estate ads for houses in Sarasota, Florida. Many houses range from $200,000 to $400,000 in price. The few houses on the water, however, have prices up to $15 million. Which of the following statements best describes the distribution of ho
(d) The distribution is most likely skewed to the right, and the mean is greater than the median.
A child is 40 inches tall, which places her at the 90th percentile of all children of similar age. The heights for children of this age form an approximately Normal distribution with a mean of 38 inches. Based on this information,what is the standard devi
(e) 1.56 inches
A large set of test scores has mean 60 and standard deviation 18. If each score is doubled, and then 5 is subtracted from the result, the mean and standard deviation of the new scores are
(b) mean 115; std. dev. 36
For a certain experiment, the available experimental units are eight rats, of which four are female (F1, F2, F3, F4) and four are male (M1, M2, M3, M4). There are to be four treatment groups, A, B, C, and D. If a randomized block design is used, with the
(c) A ? (F1, M2), B ? (F3, F2), C ? (F4, M1), D ? (M3, M4)
For a biology project, you measure the weight in grams (g) and the tail length in millimeters (mm) of a group of mice. The equation of the least-squares line for predicting tail length from weight is predicted tail length = 20 + 3 � weight Which of the fo
(a) The slope is 3, which indicates that a mouse's weight should increase by about 3 grams for each additional millimeter of tail length.
The figure below shows a Normal density curve. Which of the following gives the best estimates for the mean and standard deviation of this Normal distribution?
(c) ? = 225, ? = 50
The owner of a chain of supermarkets notices that there is a positive correlation between the sales of beer and the sales of ice cream over the course of the previous year. During seasons when sales of beer were above average, sales of ice cream also tend
(e) The positive correlation is most likely a result of the lurking variable temperature; that is, as temperatures increase, so do both beer sales and ice cream sales.
Here are the IQ scores of 10 randomly chosen fifth-grade students:145 139 126 122 125 130 96 110 118 118
Which of the following statements about this data set is not true?
(e) If the value 96 were removed from the data set, the IQR of the remaining 9 IQ scores would be lower than the IQR of all 10 IQ scores.
Before he goes to bed each night, Mr. Kleen pours dishwasher powder into his dishwasher and turns it on. Each morning, Mrs. Kleen weighs the box of dishwasher powder. From an examination of the data, she concludes that Mr. Kleen dispenses a rather consist
(d) II and III only
The General Social Survey (GSS), conducted by the National Opinion Research Center at the University of Chicago, is a major source of data on social attitudes in the United States. Once each year, 1500 adults areinterviewed in their homes all across the c
(d) stratified random sample
You are planning an experiment to determine the effect of the brand of gasoline and the weight of a car on gas mileage measured in miles per gallon. You will use a single test car, adding weights so that its total weight is 3000,3500, or 4000 pounds. The
(d) There are nine combinations of weight and gasoline. Run the car several times using each of these combinations. Make all these runs in random order.
A linear regression was performed using the five following data points: A(2, 22), B(10, 4), C(6, 14), D(14, 2), E(18, ?4). The residual for which of the five points has the largest absolute value?
(b) B
The frequency table below summarizes the times in the last month that patients at the emergency room of a small-city hospital waited to receive medical attention. Which of the following represents possible values for the median and mean waiting times for
(b) median = 28 minutes and mean = 30 minutes
Boxplots of two data sets are shown. Based on the boxplots, which statement below is true?
(a) The spread of both plots is about the same.
The five-number summary for a data set is given by min = 5, Q1 = 18, M = 20, Q3 = 40, max = 75. If you wanted to construct a modified boxplot for the data set (that is, one that would show outliers, if any existed), what would be the maximum possible leng
(a) 33
The probability distribution for the number of heads in four tosses of a coin is given by: The probability of getting at least one tail in four tosses of a coin is
(d) 0.9375.
In a certain large population of adults, the distribution of IQ scores is strongly left-skewed with a mean of 122 and a standard deviation of 5. Suppose 200 adults are randomly selected from this population for a market researchstudy. The distribution of
(e) approximately Normal with mean 122 and standard deviation 0.35.
A 10-question multiple-choice exam offers 5 choices for each question. Jason just guesses the answers, so he has probability 1/5 of getting any one answer correct. You want to perform a simulation to determine the number of correct answers that Jason gets
(b) One digit from the random digit table simulates one answer, with 0 or 1 = right and all other digits = wrong. Ten digits from the table simulate 10 answers.
Suppose we roll a fair die four times. The probability that a 6 occurs on exactly one of the rolls is
(c)
You want to take an SRS of 50 of the 816 students who live in a dormitory on a college campus. You label the students 001 to 816 in alphabetical order. In the table of random digits, you read the entries
95592 94007 69769 33547 72450 16632 81194 14873
The
(e) 400, 769, 335.
The number of unbroken charcoal briquets in a twenty-pound bag filled at the factory follows a Normal distribution with a mean of 450 briquets and a standard deviation of 20 briquets. The company expects that a certain number of the bags will be under fil
(c) 418
You work for an advertising agency that is preparing a new television commercial to appeal to women. You have been asked to design an experiment to compare the effectiveness of three versions of the commercial. Each subject will be shown one of the three
(a) a block design, but not a matched pairs design.
Suppose that you have torn a tendon and are facing surgery to repair it. The orthopedic surgeon explains the risks to you. Infection occurs in 3% of such operations, the repair fails in 14%, and both infection and failure occur together 1% of the time. Wh
(d) 0.8660
Social scientists are interested in the association between high school graduation rate (HSGR) and the percent of U.S. families living in poverty (POV). Data were collected from all 50 states and the District of Columbia, and a regression analysis was con
(c) For each 1% increase in the graduation rate, the percent of families living in poverty is predicted to decrease by approximately 0.620.
Here is a dotplot of the adult literacy rates in 177 countries in 2008, according to the United Nations. For example,the lowest literacy rate was 23.6%, in the African country of Burkina Faso. Use the dotplot below to answer Questions 25 to 27.
The overal
(b) clearly skewed to the left.
Here is a dotplot of the adult literacy rates in 177 countries in 2008, according to the United Nations. For example,the lowest literacy rate was 23.6%, in the African country of Burkina Faso. Use the dotplot below to answer Questions 25 to 27.
The mean o
(c) less than the median.
Here is a dotplot of the adult literacy rates in 177 countries in 2008, according to the United Nations. For example,the lowest literacy rate was 23.6%, in the African country of Burkina Faso. Use the dotplot below to answer Questions 25 to 27.
Based on t
(a) The five-number summary
The correlation between the age and height of children under the age of 12 is found to be r = 0.60. Suppose we use the age x of a child to predict the height y of the child. What can we conclude?
(c) The fraction of the variation in heights explained by the least-squares regression line of y on x is 0.36.
An agronomist wants to test three different types of fertilizer (A, B, and C) on the yield of a new variety of wheat. The yield will be measured in bushels per acre. Six one-acre plots of land were randomly assigned to each of the three fertilizers. The t
(d) a specific fertilizer, a plot of land, bushels per acre.
Which one of the following would be a correct interpretation if you have a z-score of +2.0 on an exam?
(e) It means that your grade is two standard deviations above the mean for this exam.
Records from a random sample of dairy farms yielded the information below on the number of male and female calves born at various times of the day. What is the probability that a randomly selected calf was born in the night or was a female?
(a)
When people order books from a popular online source, they are shipped in standard-sized boxes. Suppose that the mean weight of the boxes is 1.5 pounds with a standard deviation of 0.3 pounds, the mean weight of the packing material is 0.5 pounds with a s
(c) 3.02
A grocery chain runs a prize game by giving each customer a ticket that may win a prize when the box is scratched off. Printed on the ticket is a dollar value ($500, $100, $10) or the statement, "This ticket is not a winner."Monetary prizes can be redeeme
(b) $15.00, $53.85
A large company is interested in improving the efficiency of its customer service and decides to examine the length of the business phone calls made to clients by its sales staff. A cumulative relative frequency graph is shown below from data collected ov
(a) Less than 10 minutes.