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Question 70093This question is from textbook Statistics Principles and Methods
: Would someone please check my work on this problem to see if I'm doing it right?
A study of postoperative pain relief is conducted to determine if drug A has a significanlty longer duration of pain relief than drug B. Observations of teh hours of pain relief are recorded for 55 patients given drug A and 58 patients given drug B. The summary statistics are :
Drug A - Mean 4.64 - St. Dev. 1.25
Drug B - Mean 4.03 - St. Dev. 1.82
a)Formulate Ho and H1.
b)State the test statistic and the rejection region with α = .10
I think I have done this right, but would appreciate someone checking to see if what I'm doing is right. Here is what I have done.
The hypothesis is:
Ho:μ1-μ2=0 vs. H1:μ1-μ2>0
The test statistic is:
Z= X-Y/√S1˛/n1+S2˛/n2 = 4.64-4.03/√(1.25)˛/55+(1.82)˛/58 = 0.61/√.0284+.0572 =0.61/√.0855 = 0.61/.2924 =2.09
The rejection region is:
Rej:Z≥zα =Z≥z.10 = Z≥1.28
2.09 ≥ 1.28, so reject Ho.
Thank you.
kathyb
This question is from textbook Statistics Principles and Methods
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Question 70274: you are driving on a highway to a town that is 300 kilometers from your home.after 30 minutes you pass a free way exit that you know is 50 kilometers from your home.Assuming that you continue at the same constant speed, how long will it take for this entire trip?
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Question 70555This question is from textbook Algebra 2
:
A box of anthony thomas candy contains 9 dark chocolate creams, 6 milk chocolate creams, and 4 milk chocolates with nuts. How many ways can 5 candies be selected to meet each condition?
2 of one kind, 3 of another. This question is from textbook Algebra 2
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Question 70812: Our country has had 43 presidents. Write each president's last name on a card and place all 43 cards in a box. Note that several names ( e.g., Cleveland) occur twice. Now, randomly select 2 cards from the box.
What's the probability that the 2 names begin with the same letter?
1. G. Washington
2. J. Adams
3. T. Jefferson
4. J. Madison
5. J. Monroe
6. J.Q. Adams
7. A. Jackson
8. M. Van Buren
9. W. H. Harrison
10. J. Tyler
11. J. Polk
12. Z. Taylor
13. M. Fillmore
14. F. Pierce
15. J. Buchanan
16. A. Lincoln
17. A. Johnson
18. U.S. Grant
19. R. Hayes
20. J. Garfield
21. C. Arthur
22. G. Cleveland
23. B. Harrison
24. G. Cleveland
25. W. McKinley
26. T. Roosevelt
27. W. Taft
28. W. Wilson
29. W. Harding
30. C. Coolidge
31. H. Hoover
32. F.D. Roosevelt
33. H. Truman
34. D. Eisenhower
35. J. F. Kennedy
36. L.B. Johnson
37. R. Nixon
38. G. Ford
39. J. Carter
40. R. Reagan
41. G.H.W. Bush
42. B. Clinton
43. G.W. Bush
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Question 71089: A New York Times article about poll results states, "In theory, in 19 cases out of 20, the results from such a poll should differ by no more than one percentage point in either direction from what would have been obtained by interviewing all voters in the United States." Find the sample size suggested by this statement
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Question 71087: Question 1: Emperical Rule
Human body temperature have a mean of 98.20 degrees a standard deviation of 0.62 degrees.
a. Approximately what percentage of people have temperatures between 97.58 and 98.82 degrees? (Hint: Use a number line and the Emperical Rule.)
b. Approximately what percentage of people have temperatures between 96.34 and 98.2 degrees?
Question 2
Assume both data sets are population data sets. If necessary round any decimal answers to 3 decimal places.
Data set#1: 68, 77, 53, 52, 33, 70, 84, 78, 85, 77, 59, 55, 70
Data set#2: 3.7, 7.3, 3.4, 5.6 7.7, 3.2, 7.4, 7.3, 2.8, 5.4
What is the Mean, Median, Mode, Sum of squares, Variance and Standard Deviation for Data set#1 ?
What is the Mean, Median, Mode, Sum of squares, Variance, and Standard Deviation for Data Set#2 ?
b. For Data set #1 what is the z-score for 65? Is this an unusual data value?
c. For Data set#2 what is the z-score for 8.1? Is this an unusual data value?
Question 3: Standard Deviation for Grouped Data.
The following represents a frequency distribution:
Complete the rest of the frequency distribution.
Class /Frequency(f) / midpoint(x) / x.f / x-x / (x-x)sq/(x-x)sq.f
05-08 frequency=14 ? ? ? ? ?
09-12 frequency=9 ? ? ? ? ?
13-16 frequency=8 ? ? ? ? ?
17-20 frequency=4 ? ? ? ? ?
21-24 frequency=12 ? ? ? ? ?
25-28 frequency=5 ? ? ? ? ?
B. Use the above table to calculate the approximate values of the mean and sample standard deviation. ( You will need the midpoint values)
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Question 71223: Can someone please help me answer these questions. I received my test back and was in search of answers to these questions.
Question 1: Emperical Rule
Human body temperature have a mean of 98.20 degrees a standard deviation of 0.62 degrees.
a. Approximately what percentage of people have temperatures between 97.58 and 98.82 degrees? (Hint: Use a number line and the Emperical Rule.)
b. Approximately what percentage of people have temperatures between 96.34 and 98.2 degrees?
Question 2
Assume both data sets are population data sets. If necessary round any decimal answers to 3 decimal places.
Data set#1: 68, 77, 53, 52, 33, 70, 84, 78, 85, 77, 59, 55, 70
Data set#2: 3.7, 7.3, 3.4, 5.6 7.7, 3.2, 7.4, 7.3, 2.8, 5.4
What is the Mean, Median, Mode, Sum of squares, Variance and Standard Deviation for Data set#1 ?
What is the Mean, Median, Mode, Sum of squares, Variance, and Standard Deviation for Data Set#2 ?
b. For Data set #1 what is the z-score for 65? Is this an unusual data value?
c. For Data set#2 what is the z-score for 8.1? Is this an unusual data value?
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Question 71217: Question 1
Suppose you are taking a course in which your grade is determined from five sources:
30% from the mean of your test scores(excluding the midterm and final exam)
20% from your midterm exam score,
30% from your final exam score,
10% from your computer lab assignments and
10% from your homework assignments.
If your scores are 55(mean of test scores), 89(midterm score), 96(final exam score), 90(computer lab score), and 92(homework score), then what is the weighted mean of your scores.
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Question 71260: Can someone show me the answer to this question from a previous exam i have recently take please. thankyou.
Emperical Rule
Approximately what percentage of people have temperatures between 96.34 and 98.2 degrees?
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Question 71373: The following was gathered on the driving records of 100 drivers over the past year. The results are summarized in the table below Kilometers driven per year (100 drivers)
Less than 20,000 20000 to 50000 more than 50000 total
inclusive
accident during
past year 5 10 15 30
no accident during 15 20 35 70
past year
Total 20 30 50 100
If an individual is selected at random from the group above, determine the probability that the person
a) was in an accident during the past year.
b) drove less than 20,000 km or more than 50,000 km.
c) was in an accident during the past year and drove more than 50,000 km.
d) did not have an accident, given they had driven between 20,000 km and 50,000 km last year.
e) drove more than 50,000 km, given that they did not have an accident.
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Question 71364: You supervise 35 out of 118 workers in a health care facility. Next Monday a commitee representative will be chosen from these 118 workers. Assume that the representative is chosen at random.
a) What is the probabiltiy that one of the people you supervise will be chosen?
b) What is the probability that the representative wiil not be one of the people you supervise?
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Question 71359: A survey of 35 students at a local university showed the following majors:
Accounting 10
Finance 5
Information Systems 4
Management 6
Marketing 10
If a student is selected at random what is the probability that he or she is
a) a finance major?
b) a management or marketing major?
c) not an accounting major?
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Question 71357: A survey by the Canadian Frequent Flyers association revealed that 60% of its members made independent airline reservations last year. If two members are selected at random, what is the probability that,
a)Both made reservations last year?
b)at least one made reservations last year?
c)only one made a reservation last year?
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Question 71537: 1. Forty percent of the sales at a large insurance company have laptop computers, 65% have desktop computers and 24% have both. What percent of the sales people have either laptop or desktop computers?
2. Twenty percent of ABC Company’s employees are in Management. If an employee is in Management, there is a probability of 0.88 that he/she is a participant in the company’s stock purchase plan. Find the probability that an employee of this company is in Management and participates in the stock purchase plan.
3. Two cards are drawn in succession from a deck without replacement. What is the probability that both cards are red? If the first card will be returned, what is the probability that first card is an ace and the second is a face card?
4. In a certain university, 60% of all sophomores are enrolled in a Mathematics course, 73% are enrolled in an English course, and 49% are taking both. A student is randomly selected from this university.
a. What is the probability that the student is taking an English course, if it is known that he/she is enrolled in a Mathematics course?
b. If the student is taking an English course, what is the probability that he/she is also enrolled in a Mathematics course?
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Question 71536: 1. A coin is tossed thrice. What is the probability that at least 2 heads occur?
2. A pair of dice is rolled. What is the probability that the sum is equal to:
a. 5
b. 10
3. If a card is drawn at random from an ordinary deck of 52 cards, find the probability that it is:
a. Diamond
b. A red card
c. A heart or a spade
d. Not an ace
e. A black card or a king
4. The letters of the word HONESTY are written in slips of paper, and are placed in a box. A slip of paper is chosen at random. What is the probability that:
a. The letter is a vowel
b. The letter is a consonant
c. The letter is H
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Question 71565: i have problem with this ques..plz will u help me...
1)If P(A)=1/3 and P(B)=3/5 and p(A U B)=14/15, then what type of events they are. By what number should P(A) be multiplied to make them independent?
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Question 72378: In 1990, 5.8% of job applicants who were tested for drugs failed the test. At the 0.01 level, test the claim that the failure rate is now lower if a random sample of 1,520 current job applicants results in 58 failures. Does the result suggest that fewer job applicants now use drugs? Give the z score to 2 decimal places to, p(hat) to three decimal places, and the corresponding value of p to 4 decimal places. Also, do you conclude that fewer use drugs (Yes or No)?
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Question 72377: The Hudson Valley Bottling Company distributes root beer in bottles labeled 32 ounces. The Bureau of Weights and Measures randomly selects 50 of these bottles, measures their contents and obtains a sample mean of 31.80 ounces with a standard deviation of 0.75 ounces (assume population values for mean and standard deviation). Using a 0.01 significance level, test the Bureaus claim that the company is cheating consumers. Indicate whether you would use a z score or t score, give the value of that score and the critical value to 2 decimal places, and state whether you "Reject" or "Fail to Reject" the null hypothesis.
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Question 72532: Three cards are drawn from a standard deck of 52 cards, one at a time, with each card replaced before the next card is drawn. Find the probability of:
a) All 3 cards are red
b) The first card is a 10 of hearts, the second is a diamond, and the third is a 5.
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Question 72537: A bag contains 6 red chips, 9 white chips, and 5 blue chips. Three consecutive chips are drawn from the bag without replacement. Find each probability.
a) P ( 3 red )
b) P ( blue first, red second, blue third)
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Question 72843: 1.A coin and a 1-6 number cube are tossed.Find P(heads and a prime number grater than 2)
2.Each letter of word DIVISIBILITY is writen on seperate card and the cards are placed in a bag.Then two cards are selected randomly without repacing the first card.Find P(letter I, letter I )
3.The sum of Sue's age and Sam's age is 35.The product of their ages is 300.
If Sue is younger than Sam,how old is Sam.
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Question 72599: 1. In shipment containing 10 TV sets, 2 are defective. Two TV sets are taken for inspection in succession without replacement. What is the probability that
a. A defective TV sets shall be taken on the first draw?
b. A non-defective shall be taken on the first and a non-defective on the second?
c. A non-defective on the second given that it is a non-defective on the first?
2. Two balls are drawn in succession with replacement from a box containing 5 red, 4 blue, and 2 yellow balls. If the first ball drawn is red, then what is the probability that the second ball is drawn
a. Red
b. Blue
c. Yellow
3. If a cards is drawn from a deck of 52 playing cards, then what is the probability of getting
a. A red card and a face card
b. A diamond and a number below 6
c. A black and a spade
4. In a council meeting, 5 representatives are seniors, 4 are juniors, 3 are sophomores and 2 are freshmen. The council decided to form a committee with 4 members, If all the representative are given an equal chance of being selected as committee members, then what is the probability that
a. The members consists of different year level
b. Two are seniors and 2 are juniors
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