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Testing Claims About Proportions. In Exercises 9-32, test the given claim. Identify the null hypothesis, alternative hypothesis, test statistic, P-value, or critical value(s), then state the conclusion about the null hypothesis, as well as the final conclusion that addresses the original claim. Use the P-value method unless your instructor specifies otherwise. Use the
21. Touch Therapy When she was 9 years of age, Emily Rosa did a science fair experiment in which she tested professional touch therapists to see if they could sense her energy field. She flipped a coin to select either her right hand or her left hand, and then she asked the therapists to identify the selected hand by placing their hand just under Emily’s hand without seeing it and without touching it. Among 280 trials, the touch therapists were correct 123 times (based on data in “A Close Look at Therapeutic Touch,” Journal of the American Medical Association, Vol. 279, No. 13). Use a 0.10 significance level to test the claim that touch therapists use a method equivalent to random guesses. Do the results suggest that touch therapists are effective?
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- A marketing research company desires to know the mean consumption of milk per week among males over age 32. They believe that the milk consumption has a mean of 4 liters, and want to construct a 98% confidence interval with a maximum error of 0.07 liters. Assuming a variance of 0.64 liters, what is the minimum number of males over age 32 they must include in their sample? Round up to the next integer.arrow_forwardSuppose GRE Verbal scores are normally distributed with a mean of 461 and a standard deviation of 118. A university plans to recruit students whose scores are in the top 4 % . What is the minimum score required for recruitment? Round to the nearest whole number, if necessaryarrow_forwardNeed help with my homework thank you random sample of 6 fields of durum wheat has a mean yield of 45.5 bushels per acre and standard deviation of 7.43 bushels per acre. Determine the 80 % confidence interval for the true mean yield. Assume the population is approximately normal. Step 1: Find the critical value that should be used in constructing the confidence interval. Round to three decimal places. Step 2 of 2: Construct the 80% confidence interval. Round to one decimal place. I got 1.476 as my critical value and 41.0 and 49.9 as my confidence intervalarrow_forward
- Can someone check my work? If you draw a card with a value of four or less from a standard deck of cards, I will pay you $14. If not, you pay me $8. (Aces are considered the highest card in the deck.) Step 1 of 2: Find the expected value of the proposition. Round to two decimal places. Losses must be expressed as negative values. PT 2: If you played this game 718 times how much would you expect to win or lose? Round your answer to two decimal places. Losses must be expressed as negative values. for part 1 I got -2.92 pt 2 -2097.56arrow_forwardThe following table describes the distribution of a random sample S of 200 individuals, arranged by education level and income. Income(Dollars per Year) < High School High School Diploma Some College Bachelor’s Degree Graduate Degree Post-Graduate Degree 0-25,000 12 8 3 2 1 0 25,000-50,000 7 12 9 12 11 2 50,000-75,000 1 3 4 6 14 5 75,000-100,000 0 2 1 8 11 8 100,000-125,000 0 1 1 4 8 9 125,000-150,000 0 0 2 3 7 12 150,000+ 0 0 1 1 3 6 Let events be defined as follows: A = the event the subject makes 0-25,000 dollars per yearB = the event the subject makes 25,000-50,000 dollars per year C = the event the subject makes 50,000-75,000 dollars per yearD = the event the subject makes 75,000-100,000 dollars per yearE = the event the subject makes 100,000-125,000 dollars per yearF = the event the subject makes 125,000-150,000 dollars per yearG = the event…arrow_forwardwhat does the central limit theorem, for all samples of the same size n with n>30, the sampling distribution of x can be approximated by a normal distribution mean? What is a real life example using this theoremarrow_forward
- An investigator analyzed the leading digits from 797 checks issued by seven suspect companies. The frequencies were found to be 0, 19, 2, 50, 361, 309, 10, 22, and 24, and those digits correspond to the leading digits of 1, 2, 3, 4, 5, 6, 7, 8, and 9, respectively. If the observed frequencies are substantially different from the frequencies expected with Benford's law shown below, the check amounts appear to result from fraud. Use a 0.10 significance level to test for goodness-of-fit with Benford's law. Does it appear that the checks are the result of fraud? Leading Digit Actual Frequency Benford's Law: Distribution of Leading Digits 1 2 3 4 5 6 7 8 9 0 19 2 50 361 309 10 22 24 30.1% 17.6% 12.5% 9.7% 7.9% 6.7% 5.8% 5.1% 4.6% Determine the null and alternative hypotheses. Ho The leading digits are from a population that conforms to Benford's law. H₁: At least one leading digit has a frequency that does not conform to Benford's law. Calculate the test statistic, x². x² = (Round to three…arrow_forwardFor the distribution drawn here, identify the mean, median, and mode. Question content area bottom Part 1 A. Aequalsmode, Bequalsmedian, Cequalsmean B. Aequalsmode, Bequalsmean, Cequalsmedian C. Aequalsmedian, Bequalsmode, Cequalsmean D. Aequalsmean, Bequalsmode, Cequalsmedianarrow_forwardA study was done using a treatment group and a placebo group. The results are shown in the table. Assume that the two samples are independent simple random samples selected from normally distributed populations, and do not assume that the population standard deviations are equal. Complete parts (a) and (b) below. Use a 0.05 significance level for both parts. a. Test the claim that the two samples are from populations with the same mean. What are the null and alternative hypotheses? OA. Ho PP2 H₁: P1 P2 OC. Ho H₁₂ H₁: P₁arrow_forwardFind the regression equation, letting the first variable be the predictor (x) variable. Using the listed lemon/crash data, where lemon imports are in metric tons and the fatality rates are per 100,000 people, find the best predicted crash fatality rate for a year in which there are 475 metric tons of lemon imports. Is the prediction worthwhile? Use a significance level of 0.05. Lemon Imports 235 264 356 Crash Fatality Rate 16 15.9 15.6 476 518 15.3 D 15.1 Find the equation of the regression line. + (Round the y-intercept to three decimal places as needed. Round the slope to four decimal places as needed.) The best predicted crash fatality rate for a year in which there are 475 metric tons of lemon imports is fatalities per 100,000 population. (Round to one decimal place as needed.) Is the prediction worthwhile? OA. Since there appears to be an outlier, the prediction is not appropriate. OB. Since all of the requirements for finding the equation of the regression line are met, the…arrow_forwardA study of seat belt users and nonusers yielded the randomly selected sample data summarized in the accompanying table. Use a 0.05 significance level to test the claim that the amount of smoking is independent of seat belt use. A plausible theory is that people who smoke are less concerned about their health and safety and are therefore less inclined to wear seat belts. Is this theory supported by the sample data? Click the icon to view the data table. Determine the null and alternative hypotheses. OA. Ho: The amount of smoking is dependent upon seat belt use. H₁: The amount of smoking is not dependent upon seat belt use. OB. Ho: Heavy smokers an H₁: Heavy smokers an OC. Ho: The amount of sm H₁: The amount of sm OD. Ho Heavy smokers an H₁: Heavy smokers ar Determine the test statistic. x²= (Round to three decin More Info Number of Cigarettes Smoked per Day 0 1-14 15-34 35 and over Wear Seat Belts 193 20 42 9 Don't Wear Seat Belts 159 10 41 9 Determine the P-value of the t P-Value =…arrow_forwardAssume that the amounts of weight that male college students gain during their freshman year are normally distributed with a mean of μ = 1.3 kg and a standard deviation of o=5.5 kg. Complete parts (a) through (c) below. a. If 1 male college student is randomly selected, find the probability that he gains between 0 kg and 3 kg during freshman year. The probability is (Round to four decimal places as needed.) b. If 9 male college students are randomly selected, find the probability that their mean weight gain during freshman year is between 0 kg and 3 kg. The probability is (Round to four decimal places as needed.) c. Why can the normal distribution be used in part (b), even though the sample size does not exceed 30? OA. Since the distribution is of sample means, not individuals, the distribution is a normal distribution for any sample size. OB. Since the weight gain exceeds 30, the distribution of sample means is a normal distribution for any sample size. OC. Since the original…arrow_forwardarrow_back_iosSEE MORE QUESTIONSarrow_forward_ios
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin HarcourtHolt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL