Determine whether the data are qualitative or quantitative. 2) the number of seats in a movie theater A) quantitative B) qualitative

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1 MATH 2 FINAL EXAMINATION ANSWER ALL QUESTIONS. TIME.5 HOURS MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Identify the sampling technique used. ) Based on, responses from 8,5 questionnaires sent to its alumni, a major university estimated that the annual salary of its alumni was $8,5 per year. A) stratified B) systematic C) convenience D) cluster E) random ) Determine whether the data are qualitative or quantitative. 2) the number of seats in a movie theater A) quantitative B) qualitative 2) ) the colors of automobiles on a used car lot A) qualitative B) quantitative ) Identify whether the statement describes inferential statistics or descriptive statistics. ) There is a relationship between smoking cigarettes and getting emphysema. A) inferential statistics B) descriptive statistics ) Provide an appropriate response. 5) The mean score of a competency test is 82, with a standard deviation of 2. Between what two values do about 99.7% of the values lie? (Assume the data set has a bell-shaped distribution.) A) Between 78 and 86 B) Between 76 and 88 C) Between 7 and 9 D) Between 8 and 8 5) 6) A teacher gives a 2-point quiz to students. The scores are listed below. What percentile corresponds to the score of 2? 6) A) B) 25 C) 2 D) 7) For the mathematics part of the SAT the mean is 5 with a standard deviation of, and for the mathematics part of the ACT the mean is 2.6 with a standard deviation of 5.. Bob scores a 66 on the SAT and a 27 on the ACT. Use z-scores to determine on which test he performed better. A) ACT B) SAT 7) 8) Decide if the events A and B are mutually exclusive or not mutually exclusive. A card is drawn from a standard deck of 52 playing cards. A: The result is a club. B: The result is a king. A) mutually exclusive B) not mutually exclusive 8) 9) A coin is tossed. Find the probability that the result is heads. A) B).5 C). D).9 9)

2 ) A group of students were asked if they carry a credit card. The responses are listed in the table. ) Class Credit Card Carrier Not a Credit Card Carrier Total Freshman Sophomore 7 Total 5 55 If a student is selected at random, find the probability that he or she owns a credit card given that the student is a freshman. Round your answer to three decimal places. A).2 B).267 C).2 D).8 ) The random variable x represents the number of boys in a family of three children. Assuming that boys and girls are equally likely, find the mean and standard deviation for the random variable x. A) mean:.5; standard deviation:.76 B) mean:.5; standard deviation:.87 C) mean: 2.25; standard deviation:.76 D) mean: 2.25; standard deviation:.87 ) 2) In a certain normal distribution, find the standard deviation σ when μ = 5 and.56% of the area lies to the right of 55. A) 2 B) C) D) 5 2) ) Assume that the heights of men are normally distributed with a mean of 68.5 inches and a standard deviation of 2.8 inches. If 6 men are randomly selected, find the probability that they have a mean height greater than 69.5 inches. A).95 B) C).888 D).2 ) ) Find the z-scores for which 9% of the distributionʹs area lies between -z and z. A) (-.96,.96) B) (-.99,.99) C) (-.65,.65) D) (., 2.) ) 5) A random sample of 56 fluorescent light bulbs has a mean life of 65 hours with a standard deviation of hours. Construct a 95% confidence interval for the population mean. A) (59.6, 55.2) B) (2., 8.9) C) (72., 768.) D) (66.9, 65.) 5) 6) The ages of grooms at their first marriage are listed below. Find the midquartile. 6) A).5 B).7 C). D).2 7) The table lists the smoking habits of a group of college students. 7) Sex Non-smoker Regular Smoker Heavy Smoker Total Man Woman Total If a student is chosen at random, find the probability of getting someone who is a regular or heavy smoker. Round your answer to three decimal places. A).57 B).26 C).22 D).7 2

3 8) A test consists of 92 true or false questions. If the student guesses on each question, what is the mean number of correct answers? A) 92 B) 6 C) 8 D) 8) 9) Find the z-score that is greater than the mean and for which 7% of the distributionʹs area lies to its left. A).98 B).8 C).5 D).7 9) 2) The standard IQ test has a mean of 5 and a standard deviation of. We want to be 98% certain that we are within 2 IQ points of the true mean. Determine the required sample size. A) 2 B) C) 5 D) 6 2) 2) Find the critical X2 -values to test the claim σ2 6.8 if n = and α =.. A).75, B).25, 6.99 C) 2.7, 9.2 D) 2.88, ) 22) Classify the events as dependent or independent. Events A and B where P(A) =.2, P(B) =.6, and P(A and B) =.2 A) dependent B) independent 22) 2) According to government data, the probability that a woman between the ages of 25 and 29 was never married is %. In a random survey of women in this age group, what is the probability that at least eight were married? A).67 B).2 C).6 D). 2) 2) For the standard normal curve, find the z-score that corresponds to the 7th decile. A).98 B).5 C).2 D).7 2) Assume the sample is taken from a normally distributed population and construct the indicated confidence interval. 25) A student randomly selects CDs at a store. The mean is $.75 with a standard deviation of 25) $.5. Construct a 95% confidence interval for the population standard deviation, σ. A) ($.6, $7.5) B) ($.99, $2.5) C) ($.8, $2.2) D) ($., $2.7) Provide an appropriate response. 26) Find the critical X2 -value to test the claim σ2 >.9 if n = 8 and α =.. A) B).9 C).8 D) ) Calculate the correlation coefficient, r, for the data below. 26) 27) x y A) -.2 B) -. C) -.58 D) ) A coffeehouse wishes to see if customers have any preference among 5 different brands of coffee. A sample of 2 customers provided the data below. Calculate the chi-square test statistic χ2 to test the claim that the distribution is uniform.. 28) Brand 2 5 Customers A) 5.9 B) 55.6 C) 8.9 D) 7.5

4 29) A researcher wants to determine whether the number of minutes adults spend online per day is related to gender. A random sample of 5 adults was selected and the results are shown below. 29) Find the critical value χ 2 to determine if there is enough evidence to conclude that the number of minutes spent online per day is related to gender. Use α =.5. Minutes spent online per day Gender Male Female A) 7.85 B) 6.25 C).5 D) 9.8 ) The contingency table below shows the results of a random sample of 2 state representatives that was conducted to see whether their opinions on a bill are related to their party affiliation. ) Party Republican Democrat Independent Opinion Approve Disapprove No Opinion Find the critical value χ 2, to test the claim of independence using α =.5. A) 9.88 B).277 C) D). ) Given a sample with r = -.765, n = 22, and α =.2, determine the standardized test statistic t necessary to test the claim ρ =. Round answers to three decimal places. A).65 B) -.78 C).2 D) -.92 ) 2) Use the regression equation to predict the value of y for x = -.. Assume that the variables x and y have a significant correlation. 2) x y A).97 B) -.96 C).57 D).89 ) Given the equation of a regression line is y^ =.5x - 5., what is the best predicted value for y given x = -.2? Assume that the variables x and y have a significant correlation. A). B) 2. C) -9.6 D).9 )

5 Answer Key Testname: M2F ) E 2) A ) A ) A 5) B 6) A 7) B 8) B 9) B ) C ) B 2) C ) D ) C 5) D 6) D 7) C 8) B 9) C 2) A 2) A 22) B 2) A 2) B 25) D 26) B 27) B 28) D 29) A ) A ) C 2) A ) C 5