Assignment is a statists test, attached PDF is the test form and answers will need to be filled out on the accompanying Excel sheet.
Test 2 B58 Test 2 - Bus 215 Name _____________________________ A.M. Ward Chapters 5-8 1. If two events A and B are mutually exclusive, what does the special rule of addition state? A. P(A or B) = P(A) + P(B) B. P(A and B) = P(A) + P(B) C. P(A and/or B) = P(A) + P(B) D. P(A or B) = P(A) – P(B) 2. Which approach to probability is exemplified by the following formula? Probability of an Event = Number of times an event occurred in the past Total number of observations A. Classical approach B. Empirical approach C. Subjective approach D. None of the above 3. A lamp manufacturer has developed five lamp bases and three lampshades that could be used together. How many different arrangements of base and shade can be offered? A. 5 B. 10 C. 15 D. 20 4. The first card selected from a standard 52-card deck was a king. If it is returned to the deck, what is the probability that a king will be drawn on the second selection? A. 1/4 or 0.25 B. 1/13, or 0.077 C. 12/13, or 0.923 D. 1/3 or 0.33 5. An experiment may have (after the experiment is done): A. Only one result B. Only two results C. Two or more results D. None of the above 6. When are two events mutually exclusive? A. They overlap on a Venn diagram B. If one event occurs, then the other cannot C. Probability of one affects the probability of the other D. Both (a) and (b) 7. The result of a particular experiment is called a(n) A. observation. B. conditional probability. C. event. D. outcome. 8. The probability of two or more events occurring concurrently is called a(an) A. conditional probability. B. empirical probability. C. joint probability. D. tree diagram. E. none of the above. 9. A graphical method useful in calculating joint and conditional probability is A. a tree diagram. B. a Venn diagram. C. a histogram. D. inferential statistics. 10. When applying the special rule of addition for mutually exclusive events, the joint probability is: A. 1 B. .5 C. 0 D. unknown 11. If the variance of a probability was computed to be 36 grams, what is the standard deviation? A. 0.6 B. 1.9 C. 6.0 D. 12.96 12. Sixty percent of the customers of a fastfood chain order the Whopper, french fries and a drink. If a random sample of 15 cash register receipts is selected, what is the probability that 10 or more will show that the above three food items were ordered? A. 1,000 B. 0.186 C. 0.403 D. 0.000 13. The probabilities and the number of automobiles lined up at a Lakeside Olds at opening time (7:30 a.m.) for service are: Number Probability 1 0.05 2 0.40 3 0.30 4 0.25 On a typical day, how many automobiles should Lakeside Olds expect to be lined up at opening? A. 2.75 B. 1.00 C. 2.85 D. 1.96 14. An insurance agent has appointments with four prospective clients tomorrow. From past experience the agent knows that the probability of making a sale on any appointment is 1 out of 5. Using the rules of probability, what is the likelihood that the agent will sell a policy to 2 of the 4 prospective clients? A. 0.500 B. 0.154 C. 0.410 D. 0.026 15. In which of the following discrete distribution does the probability of a success NOT vary from one trial to the next? A. Binomial B. Uniform C. Hypergeometric D. All of the above 16. Which of the following is a requirement for use of the hypergeometric distribution? A. Only 2 possible outcomes B. Trials are independent C. Probability of a success is greater than 1.0 D. All of the above 17. Which is true for a binomial distribution? A. There are three or more possible outcomes B. Probability of success remains the same from trial to trial C. Value of p is equal to 1.50 D. All of the above are correct 18. The weight of an offensive linesman may be 205 pounds, 210 pounds, 225 pounds or 219 pounds. What is this an illustration of? A. Continuous random variable B. Discrete random variable C. Complement rule D. All of the above 19. Chances are 50-50 that a newborn baby will be a girl. For families with five children, what is the probability that all the children are girls? A. 0.900 B. 0.031 C. 0.001 D. 0.250 20. A new car was put into production. It involved many assembly tasks. Each car was inspected at the end of the assembly line and the number of defects per unit was recorded. For the first 100 cars produced, there were 30 defective cars. Some of the cars had no defects; a few had one defect, and so on. The distribution of defects followed a Poisson distribution. Based on the first 100 produced, about how many out of every 1,000 cars assembled should have one or more defects? A. About 660 B. About 165 C. About 260 D. About 330 21. A manufacturer of headache medicine claims it is 70 percent effective within a few minutes. That is, out of every 100 users 70 get relief within a few minutes. A group of 12 patients are given the medicine. If the claim is true, what is the probability that 8 have relief within a few minutes? A. 0.001 B. 0.168 C. 0.667 D. 0.231 22. A true-false test consists of six questions. If you guess the answer to each question, what is the probability of getting all six questions correct? A. 0 B. 0.016 C. 0.062 D. 0.250 23. What is the only variable in the Poisson probability formula? A. n B. x C. e D. P 24. In a Poisson distribution the mean is equal to A. n? B. Σx/N C. e - x. D. µxe-µ/x! 25. The shape of any uniform probability distribution is A. Negatively skewed B. Positively skewed C. Rectangular D. Bell shaped 26. The mean of any uniform probability distribution is A. (b - a)/2 B. (a + b)/2 C. D. n 27. The standard deviation of any uniform probability distribution is A. (b – a)/2 B. n ( 1 – ) C. D. 28. The upper and lower limits of a uniform probability distribution are A. positive and negative infinity B. plus and minus three standard deviations. C. 0 and 1 D. the maximum and minimum values of the random variable. 29. What is an important similarity between the uniform and normal probability distributions? A. The mean, median and mode are all equal. B. The mean and median are equal C. They are negatively skewed D. About 68% of all observations are within one standard deviation of the mean. 30. For the normal distribution, the mean plus and minus 1.96 standard deviations will include about what percent of the observations? A. 50% B. 99.7% C. 95% D. 68% 31. For a standard normal distribution, what is the probability that z is greater than 1.75? A. 0.0401 B. 0.0459 C. 0.4599 D. 0.9599 32. What is the area under the normal curve between z = 0.0 and z = 2.0? A. 1.0000 B. 0.7408 C. 0.1359 D. 0.4772 33. The mean amount spent by a family of four on food per month is $500 with a standard deviation of $75. Assuming that the food costs are normally distributed, what is the probability that a family spends less than $410 per month? A. 0.2158 B. 0.8750 C. 0.0362 D. 0.1151 34. Which of the following is NOT a characteristic of the normal probability distribution? A. Positively-skewed B. Bell-shaped C. Symmetrical D. Asymptotic 35. The mean of a normally distributed group of weekly incomes of a large group of executives is $1,000 and the standard deviation is $50. What is the z-score for an income of $1,100? A. 1.00 B. 2.00 C. 1.683 D. -0.90 36. Tables of normal distribution probabilities are found in many statistics books. These probabilities are calculated from a normal distribution with A.