Stat 200 Midterm Exam with all the correct answers(Real Exam)

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Stat 200 – Midterm Dr. T Name: Multiple-Choice: Choose exactly one answer for each question. There are 33 problems for 3 points each. Total 33×3+1=100 points 01. A few of the variables for whic... h data were collected in a certain study include age, gender, income, and number of hours spent shopping online per month. Which of the variables is qualitative? A. Age. B. Gender. C. Income. D. Number of hours spent shopping online. E. None. 02. The Human Resources Department of a large corporation maintains records on its employees. Data are maintained of the following variables: Age, Employment Category, Education, Whether or not the employee participates in a wellness program, and Paycheck benefit deductions. Which of these variables are quantitative? A. Age, Employment Category, and Education. B. Employment Category, Education, and Whether or not the employee participates in a wellness program. C. Education, Whether or not the employee participates in a wellness program, and Paycheck benefit deductions. D. Age, Paycheck benefit deductions. E. None of the above. 03. Suppose that a company has an alphabetized list of regular customers who belong to their rewards program. They plan to survey a sample of 120 of those customers. After randomly selecting a customer on the list, every 25th customer from that point on is chosen to be in the sample. This sampling plan is called A. SimpleRandomSampling. B. Stratified Sampling. C. Cluster Sampling. D. Systematic Sampling. E. Convenience Sampling. Page 1 of 8 04. The collection of all subjects that are being studied is A. The sample. B. The population. C. Statistical inference. D. Descriptive statistics. E. None of the above. 05. Statistical studies in which researchers do not control variables of interest are A. Experimentalstudies. B. Uncontrolled experimental studies. C. Arbitrarystudies. D. Observational studies. E. None of the above. 06. Statistical studies in which researchers control variables of interest are A. Experimentalstudies. B. Controlobservationalstudies. C. Non-experimentalstudies. D. Observational studies. E. None of the above. 07. A data set consists of scores on a Math test and the scores range from 20 to 96. We wish to construct a frequency distribution with 8 classes. Find the most suitable upper and lower class boundaries for the first class. A. 20 - 29 B. 20.5 – 29.5 C. 19.5 – 29.5 D. 20 - 30 E. 19.5 – 30.5 08. A measurement obtained by using all the data values for a specific population is called A. A variable. B. The mean. C. The standard deviation. D. A statistic. E. A parameter. 09. The measure of central location which is most likely to be influenced by extreme values is A. the mode B. the median C. the mean D. all of the above E. none of the above Use the data in the table below to answer the next three questions. The table below shows closing share prices for a small sample of companies. COMPANY 3M Dental Products Tyco Electronics Power Systems Kyocera America Inc. Pfizer Inc. Xerox Company Northrop Grumman Corporation Lockheed Martin Maritime Systems Sony DADC Matsushita Electronic Components Foster Wheeler Environmental Corp. 10. The mean closing share price is A. $31.23 B. $44.65 C. $56.99 D. $62.19 E. $75.77 CLOSING SHARE PRICE – 08/07 86.95 47.45 94.10 22.39 17.56 75.81 100.17 51.91 17.91 55.67 11. The standard deviation in closing share prices is A. $31.43 B. $44.65 C. $56.99 D. $62.19 E. $75.77 12. The z score for the share price for Matsushita Electronic Components is A. 1.24 B. 2.34 C. -2.34 D. -3.00 E. -1.24. 13. One of the most widely used measures of dispersion is A. the mean B. the range C. the z-score D. the standard deviation E. the IQR 14. In England 16% of the people eat lamb, in France 20%, in Greece 35%, and in Australia 30%. The graphical device(s) which can be used to present these data is (are) A. a line chart B. only a bar chart C. only a pie chart D. both a bar chart and a pie chart E. a histogram 15. A recent survey of local cell phone retailers showed that of all cell phones sold last month, 64% had a camera, 28% had a music player and 18% had both. The probability that a cell phone sold last month had a camera or a music player is A. 0.92 B. 0.70 C. 0.74 D. 0.36 E. None of the above 16. To speed up the process in a blood testing procedure, blood samples from 3 people are combined into one mixture. The mixture will only test negative if all the individual samples are negative. If the probability that an individual sample tests positive is 10%, what is the probability that a mixture of three will test positive? A 0.300 B 0.100 C 0.271 D 0.001 E 0.729 Use the following information to do the next two problems: A survey of 800 College seniors produced the following contingency table (cross-tabulation) regarding their undergraduate major and whether or not they planned to go to graduate school. 17. Given that a student is majoring in Business, what is the probability that he/she plans to go to graduate school? A. 27.78% B. 8.75% C. 70% D. 72.22% E. none of the above 18. Given that a student plans to go to graduate school, what is the probability that he/she indicated “Other” majors? A. 15.75% B. 45% C. 49.22% D. 32% E. none of the above 19. In how many different ways can a work party of 3 be chosen from 8 volunteers? A. 3 B. 24 C. 336 D. 56 E. None of the above 20. Which of the following is/are properties of the Binomial Distribution? A. The number of trials is fixed in advance. B. The trials are independent. C. Each trial has exactly two outcomes. D. The probability of success is the same for each trial. E. All of the above. 21. Find the probability of at most 2 girls in 6 births. Assume that male and female births are equally likely and that the births are independent events. A. 0.234 B. 0.109 C. 0.333 D. 0.657 E. 0.344 22. A test consists of 10 true/false questions. To pass the test a student must answer at least 8 questions correctly. If a student guesses on each question, what is the probability that the student will pass the test? A. 0.011. B. 0.044. C. 0.055. D. 0.800. E. none of the above 23. The number of armed robberies and their probabilities, in a particular city in any given month, are given in the table below: Number of armed robberies Probability 1 0.05 2 0.30 3 0.40 4 0.25 How many armed robberies on the average should be expected on a typical month? A. 5.00 B. 2.50 C. 2.85 D. 3.01 E. None of the above 24. Find the standard deviation of the above distribution. A. 0.73 B. 0.77 C. 0.80 D. 0.85 E. None of the above 25. A gambler pays $5 to play a game of dice. If he rolls a sum of 10 the house pays him $10, if he rolls a sum of 3 the house pays him $20, otherwise he loses. What is the expectation of this game? A -$2.36 B $2.36 C -$2.78 D -$3.06 E none of the above 26. Find the value of z such that the area between –z and +z is 97.6% of the total area under the standard normal curve. A. 2.25 B. 1.96 C. 2.58 D. 2.36 E. 2.26 27. An auditor takes a random sample of size n=110 from a large population. The population standard deviation is not known, but the sample standard deviation is s = 48. Find the standard error of the mean. A. 48 B. 4.58 C. 0.44 D. 2.29 E. None of the above 28. The mean amount spent by a family of four on food per month is $500 with a standard deviation of $75. Assuming a normal distribution, what is the probability that a family spends more than $410 per month? A. 0.1151 B. 0.1539 C. 0.8849. D. 0.8461 E. none of the above 29. The scores on a certain test are normally distributed with mean 61 and standard deviation 3. What is the probability that a sample of 100 students will have a mean score more than 61.3? A. 0.4602 B. 0.3413 C. 0.8413 D. 0.1587 E. none of the above. 30. A random sample of 66 observations was taken from a large population. The population proportion is 12%. The probability that the sample proportion will be more than 17% is A. 0.0568 B. 0.8944 C. 0.1056 D. 0.4222 E. None of the above 31. Assume a Normal Distribution with mean μ = 98.7 and IQR = 0.67. Find the standard deviation. A. 0.37 B. 0.45 C. 0.50 D. 1.50 E. none of the above 32. As the sample size increases, A. the population standard deviation decreases B. the population standard deviation increases C. the standard error increases. D. the standard error decreases. E. none of the above 33. Statistical inference A. is reasoning from a sample to a population. B. is reasoning from a population to a sample. C. requires a large sample. D. requires examination of the entire population. E. is based on deductive reasoning. [Show More]

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