Name. SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.

Transcription

1 Exam I Math 1342 HCCS Name Date SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. Determine whether the numerical value is a parameter or a statistic. Explain your reasoning. 1) A survey of 1162 students was taken from a university with 10,000 students. 1) MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Identify whether the statement describes inferential statistics or descriptive statistics. 2) The chances of winning the California Lottery are one chance in twenty-two million. A) inferential statistics B) descriptive statistics 2) 3) From past figures, it is predicted that 19% of the registered voters in California will vote in the June primary. A) inferential statistics B) descriptive statistics 3) Determine whether the data are qualitative or quantitative. 4) the number of complaint letters received by the United States Postal Service in a given day A) qualitative B) quantitative 4) 5) the numbers on the shirts of a girl's soccer team A) quantitative B) qualitative 5) Identify the data set's level of measurement. 6) ages of students in a statistic class A) ordinal B) interval C) ratio D) nominal 6) 7) the final grades (A, B, C, D, and F) for students in a statistics class A) interval B) ratio C) ordinal D) nominal 7) 8) list of zip codes for Chicago A) nominal B) interval C) ratio D) ordinal 8) 9) the years the summer Olympics were held in the United States A) ratio B) nominal C) ordinal D) interval 9) 10) the lengths (in minutes) of the top ten movies with respect to ticket sales in 2007 A) nominal B) ordinal C) interval D) ratio 10) A-1

2 Decide which method of data collection you would use to collect data for the study. Specify either observational study, experiment, simulation, or survey. 11) A study where a political pollster wishes to determine if his candidate is leading in the polls 11) A) observational study B) survey C) simulation D) experiment 12) A study where you would like to determine the chance getting three girls in a family of three children A) experiment B) observational study C) simulation D) survey 12) Identify the sampling technique used. 13) Thirty-five sophomores, 50 juniors and 37 seniors are randomly selected from 538 sophomores, 448 juniors and 394 seniors at a certain high school. A) convenience B) cluster C) random D) systematic E) stratified 13) 14) A researcher for an airline interviews all of the passengers on five randomly selected flights. A) systematic B) stratified C) cluster D) random E) convenience 14) 15) To ensure customer satisfaction, every 20th phone call received by customer service will be monitored. A) systematic B) convenience C) stratified D) cluster E) random 15) 16) A researcher randomly selected 25 of the nation's middle schools and interviewed all of the teachers at each school. A) convenience B) random C) cluster D) systematic E) stratified 16) A-2

3 Use the given frequency distribution to find the (a) class width. (b) class midpoints of the first class. (c) class boundaries of the first class. 17) Height (in inches) Class Frequency, f A) (a) 2 (b) 51.5 (c) B) (a) 3 (b) 51 (c) C) (a) 2 (b) 51.5 (c) D) (a) 3 (b) 51 (c) ) 18) Miles (per day) Class Frequency, f A) (a) 2 (b) 1 (c) 1-2 B) (a) 1 (b) 1.5 (c) C) (a) 2 (b) 1.5 (c) D) (a) 1 (b) 1 (c) ) Provide an appropriate response. 19) Use the ogive below to approximate the cumulative frequency for 24 hours. 19) A) 17 B) 27 C) 75 D) 63 A-3

4 20) The top 14 speeds, in miles per hour, for Pro-Stock drag racing over the past two decades are listed below. Find the median speed. 20) A) B) C) D) ) The scores of the top ten finishers in a recent golf tournament are listed below. Find the mode score. 21) A) 72 B) 73 C) 67 D) 76 22) The mean IQ score of adults is 100, with a standard deviation of 15. Use the Empirical Rule to find the percentage of adults with scores between 70 and 130. (Assume the data set has a bell-shaped distribution.) A) 100% B) 99.7% C) 68% D) 95% 22) 23) The mean IQ score of students in a particular calculus class is 110, with a standard deviation of 5. Use the Empirical Rule to find the percentage of students with an IQ above 120. (Assume the data set has a bell-shaped distribution.) A) 13.5% B) 11.15% C) 15.85% D) 2.5% 23) 24) 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 80 and 84 B) Between 76 and 88 C) Between 78 and 86 D) Between 74 and 90 24) 25) The mean monthly rent for a sample of studio apartments in one city is $1260 with a standard deviation of $230. The monthly rents for eight more studio apartments in the city are listed. Using the sample statistics above, determine which of the data values are unusual. Are any of the data values very unusual? Explain. (Assume the data set has a bell-shaped distribution.) $1099, $1651, $1743, $1973, $846, $1789, $1398, $685 A) $1973 is unusual because it is more than 3 standard deviations from the mean. There are no values that are very unusual because no value is more than 4 standard deviations from the mean. B) $1651, $1743, $1973, $846, $1789, $685 are unusual because they are more than 1 standard deviation from the mean. $1743, $1973, $1789, $685 are very unusual because they are more than 2 standard deviations from the mean. C) $1743, $1973, $1789, $685 are unusual because they are more than 2 standard deviations from the mean. $1973 is very unusual because it is more than 3 standard deviations from the mean. D) $1743, $1973, $846, $1789, $685 are unusual because they are more than 2 standard deviations from the mean. $1973 and $685 are very unusual because they are more than 3 standard deviations from the mean. 25) A-4

5 26) In a random sample, 10 students were asked to compute the distance they travel one way to school to the nearest tenth of a mile. The data is listed below. 26) a) If a constant value k is added to each value, how will the standard deviation be affected? b) If each value is multiplied by a constant k, how will the standard deviation be affected? A) The standard deviation will be multiplied by the constant k. B) The standard deviation will not be affected. 27) The test scores of 30 students are listed below. Find the five-number summary. 27) A) Min = 31, Q1 = 58, Q2 = 72, Q3 = 83, Max = 99 B) Min = 31, Q1 = 57, Q2 = 70, Q3 = 81, Max = 99 C) Min = 31, Q1 = 58, Q2 = 70, Q3 = 83, Max = 99 D) Min = 31, Q1 = 57, Q2 = 72, Q3 = 81, Max = 99 28) The cholesterol levels (in milligrams per deciliter) of 30 adults are listed below. Find Q1. 28) A) B) 200 C) 171 D) ) Find the z-score for the value 55, when the mean is 58 and the standard deviation is 3. A) z = 0.90 B) z = C) z = D) z = ) SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 30) Test scores for a history class had a mean of 79 with a standard deviation of 4.5. Test scores for a physics class had a mean of 69 with a standard deviation of 3.7. Suppose a student gets a 83 on the history test and a 84 on the physics test. Calculate the z-score for each test. On which test did the student perform better? 30) MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 31) The birth weights for twins are normally distributed with a mean of 2353 grams and a standard deviation of 647 grams. Use z-scores to determine which birth weight could be considered unusual. A) 2353 g B) 1200 g C) 2000 g D) 3647 g 31) A-5

6 32) The ages of 10 grooms at their first marriage are listed below. Find the midquartile. 32) A) 34.2 B) 43.7 C) 34.5 D) ) The cholesterol levels (in milligrams per deciliter) of 30 adults are listed below. Find D6. 33) A) 200 B) 171 C) 205 D) 265 Use the grouped data formulas to find the indicated mean or standard deviation. 34) The manager of a bank recorded the amount of time a random sample of customers spent waiting in line during peak business hours one Monday. The frequency distribution below summarizes the results. Approximate the sample mean. Round your answer to one decimal place. 34) Waiting time (minutes) Number of customers A) 7.7 min B) 9.0 min C) 13.5 min D) 9.2 min A-6

7 Answer Key Testname: 1342-TEST 1-CHS ) It describes a statistic because the number 1162 is based on a subset of the population. 2) A 3) A 4) B 5) B 6) C 7) C 8) A 9) D 10) D 11) A 12) C 13) E 14) C 15) A 16) C 17) B 18) C 19) D 20) B 21) A 22) D 23) D 24) B 25) C 26) B 27) A 28) D 29) C 30) history z-score = 0.89; physics z-score = 4.05; The student performed better on the physics test. 31) D 32) A 33) A 34) B A-7