AP STATS FINAL REVIEW/ AP STATISTICS –FINAL STUDY GUIDE (V.2)

AP STATS FINAL REVIEW/ AP STATISTICS –FINAL STUDY GUIDE (V.2) ) A scientist recorded the duration of the eruption of the Old Faithful geyser in Yellowstone National Park that occurred during a one-month time period. The histogram below shows the distribution of the duration, in seconds, of the eruptions. - ANSWERS(E) The distribution displays two clusters, with one cluster centered at about 125 seconds and the other centered at about 260 seconds, and has a range of at most 250 seconds. 2) Which of the variables you collect are continuous data? - ANSWERS(D) Only average annual income 3) What are the categorical variables in your survey? - ANSWERS(D) Everything but average annual income and family size 4) Given that the median is 270 and the interquartile range is 20, which of the following statements is true? - ANSWERS(A) Fifty percent of the data are greater than or equal to 270. 5) In population H, what is the height, to the nearest tenth of an inch, of the 70th percentile? - ANSWERS(A) 67.3 inches 6) In population H, what is the z-score, to the nearest tenth, associated with the height 65 inches? - ANSWERS(D) z = -0.4 7) To the nearest whole number, what percentile is associated with z = -0.68? - ANSWERS(D) 25th percentile 8) Why is the IQR considered to be a resistant statistic? - ANSWERS(A) Adding a new extreme observation has little effect on it 9) Events D and E are independent, with P(D) = 0.6 and P(D and E) = 0.18. Which of the following is true? - ANSWERS(D) P(D or E) = 0.72 10) An airline recorded the number of on-time arrivals for a sample of 100 flights each day. The boxplot below summarizes the records data for one year. - ANSWERS(E) The difference between the median and the lower quartile for the number of on-time arrivals is less than 2. 11) Which of the following can outliers affect significantly? - ANSWERS(D) I, III, and IV 12) Given these parallel boxplots, which of the following is incorrect? - ANSWERS(C) Both sets are skewed to both lower and higher values. 13) Which of the following is true about the areas described under the normal curve? - ANSWERS(D) Fewer than one percent of the cases are located three standard deviations above or below the mean. AP STATS FINAL REVIEW/ AP STATISTICS –FINAL STUDY GUIDE (V.2) 14) In which of the following histograms is the mean less than the median? - ANSWERSSKEW TO THE LEFT 15) A random sample of golf scores gives the following summary statistics: n=20, x ̅=84.5, S_x=11.5, minX=68,Q_1=78,Med=86,Q_3=91,maxX=112. What can be said about the number of outliers? - ANSWERS(D) At least 1 19) A tropical storm is classified as major if it has sustained winds greater than 110 miles per hour. Based on data from the past two decades, a meteorologist estimated the following percentages about future storms. - ANSWERS(C) 0.170 20) To which of the histograms below can the boxplot correspond? - ANSWERSMOST AT 50-60 AND 0-10 22) Research indicates that the standard deviation of typical body temperate is 0.4 degrees Celsius (C). Which of the following represents the standard deviation of typical human body temperature in degrees Fahrenheit (F), where F=9/5 C+32? - ANSWERS(B) 9/5(0.4) 24) An AP Statistics teacher grades using z-scores. On the second major exam of the marking period, a student receives a grade with a z-score of -1.3. What is the correct interpretation of this grade? - ANSWERS(E) The student scored 1.3 standard deviations lower on the second exam than the class average on the second exam. 25) The number of adults living in homes on a randomly selected city block is described by the following probability distribution. - ANSWERS(D) 0.89 26) Given two independent random variables, X with mean 12.3 and standard deviation 0.5 and Y with mean 9.1 and standard deviation 0.3, which of the following is a true statement? - ANSWERS(E) The variance of X-Y is 0.34 28) Suppose the scores on an exam have a mean of 75 with a standard deviation of 8. If one student has a test result with a z-score of -1.5, and a second student has a test result with a z-score of 2.0, how many points higher was the second student's result than that of the first? - ANSWERS(E) 28 29) A national achievement test is administered annually to 3rd graders. The test has a mean score of 100 and a standard deviation of 15. If Jane's z-score is 1.20, what was her score on the test? - ANSWERS(E) 118 30) An advantage to using surveys as opposed to experiments is that - ANSWERS(A) 82 31) Suppose X and Y are independent random variables. The variance of X is equal to 16; and the variance of Y is equal to 9. Let Z = X - Y. - ANSWERS(B) 5.00 32) A company wishes to survey what people think about a new product it plans to market. They decide to randomly sample from their customer database as this