Question

please just answer 16, 17, 18, 23

r 4 16. Suppose that the scores of architects on a particular crcativity test are normally distributcd. Using a normal curve table, what percentage of architects have Z scores (a) above.10, (b) below .10, (c) above .20, (d) below.20, (e) above 1.10 () below i.10, (g) above-10, and (h) beiow-.10? 17. In the example in problem 16, using a normal curve table, what is the minimum Z score an architect can have on the creativity test to be in the (a) top 50% (b) top 40%, (e) top 60%, (d) top 30 %, and (e) top 20%? 18. In the example in problem 16, assume that the incan is 300 and the standard devi- ation is 25. Using a normal curve table, whut scores would be the top and bottom score to fiad (a) the middle 50% of architects, (b) the middle 90% of architects and (e) the middle 99% of architects? 19. Suppose that you are designing an instrument panel for a large industrial machine. The machine requires the person using it to reach 2 feot from a particular posi tion. The reach from this position for adalt women is known to have a mean of 2.8 fet with a standard deviation of 5. The reach for adult men is known to have a mean of 3.1 feet with a standard deviation of 6. Both women's and men's reach from this position is nonnally distributed. If this design is impleinented, (a) what percentage of women will aot be able to work on this instrument pancl? (b) Wisat percentage of men will not be able to work on this instrument panel? (e) Explain your answors to a person who has never had a course in statistics 20. Supposo you want to conduct a survey of the voting preference of undergraduate students. One approach would be to contact every undergraduate student you know and ask them to fill out a questionnaire. (a) What kind of sampling method is this? (b) What is a major limitation of this kind of approach? 21. A large study of concerns about terrorism among individuals living in Los Ange les (Eisenmann ct al., 2009) recruited participants using "...a random digit dial survey of the Los Angeles population October 2004 through January 2005 in 6 languages" These are procedures in which phone numbers to call potentin! par- ticipants are randomly generated by a computer. Explain to a penson who has never had a course in statistics (a) why this method of sampling might be nsed and (b) why it may be a problem if not everyone called agreed to be interviewod. 22. Suppose that you were going to conduct a survey of visitors to your campus. You want the survey to be as ropresentative as possible. (a) How would you select the people to survey? (b) Why would that be your best method? 23. You are conducting a survey at a college with 800 students, 50 faculty members and I50 administrators. Each of these 1,000 individuals has a single listing in the campas phone directory. Supposo you were to cut up the directory and pull out one listing at random to contact. What is the probability it would be (a) a student (b) a faculty member, (c) an administrator, (d) a faculty or administrator, and (e) anyone except an administrator? () Explain your answor to part (d) to some one who has never had a course in statistics. 24. You apply to 20 graduate programs, 10 of which are in the United States, 5 of which are in Canada, and 5 of which are in Australia. You get a message from home that you have a letter from one of the programs to which you applied, but nothing is said about which one. Give the probability it is from (a) a program in the United States, (b) a program in Canada, (c) from any program other than in Australia. (d) Explain your answer to (c) to someone who has never had a course in statistics.

Answer 1

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