
Concept explainers
A city ordinance requires that a smoke detector be installed in all residential housing. There is concern that too many residences are still without detectors, so a costly inspection program is being contemplated. Let p be the proportion of all residences that have a detector. A random sample of 25 residences is selected. If the sample strongly suggests that p < 0.80 (less than 80% have detectors), as opposed to p ≥ 0.80, the program will be implemented. Let x be the number of residences among the 25 that have a detector, and consider the following decision rule: Reject the claim that p = 0.8 and implement the program if x ≤ 15. (Round your answers to three decimal places.)
a.)What is the
b.)What is the probability that the program is not implemented if p = 0.60?

Trending nowThis is a popular solution!
Step by stepSolved in 3 steps with 1 images

- The records of a light bulb manufacturer show that, when the manufacturing machinery is working correctly, the defect rate (due to imperfections in the material used) is 1%. The manufacturer's control department periodically tests samples of the bulbs, and when 1.5% or more are defective, they call repair technicians for service.The control department is going to take a random sample of 4400 light bulbs. Let p be the proportion of defective light bulbs in the sample assuming the machinery is working correctly. Answer the following.arrow_forwardPlease give an answer with a calculation and give an explanation of the correct and incorrect option.arrow_forwardAn airline claims that luggage is rarely lost (does not arrive at the destination at the same time as the passenger). The airline claims that if luggage is lost, in 87% of cases the airline is able to recover and deliver the luggage within 24 hours. A consumer watchdog group found a random sample of 125 people whose luggage was lost and found that 99 of them had their luggage recovered and returned within 24 hours. The Sample proportion p-hat is 99/125 = 0.792. The watchdog group wants to perform a hypothesis test against the claim that the airline is able to recover 87% of lost luggage in 24 hours. What is the test statistic?arrow_forward
- When two births are randomly selected, the sample space for genders is bb, bg. gb, and gg. Assume that those four outcomes are equally likely. Construct a table that describes the sampling distribution of the sample proportion of girls from two births. Does the mean of the sample proportions equal the proportion of girls in two births? Does the result suggest that a sample proportion an unbiased estimator of a population proportion? For the entire population, assume the probability of having a boy is the probability of having a girl is , and this is not affected by how many boys or girls have previously been born. 2 Determine the probabilities of each sample proportion. Probability Sample proportion of girls Tune intanare or cimnlifiad frartinnearrow_forwardThe records of a light bulb manufacturer show that, when the manufacturing machinery is working correctly, the defect rate (due to imperfections in the material used) is 1%. The manufacturer's control department periodically tests samples of the bulbs, and when 1.25% or more are defective, they call repair technicians for service. The control department is going to take a random sample of 4400 light bulbs. Let p be the proportion of defective light bulbs in the sample assuming the machinery is working correctly. A) find the mean of p b)find the standard deviation of p c)Compute an approximation for P≥p0.0125, which is the probability that, assuming the machinery is working correctly, the repair technicians will be called. Round your answer to four decimal places.arrow_forwardThe records of a light bulb manufacturer show that, when the manufacturing machinery is working correctly, the defect rate (due to imperfections in the material used) is 1%. The manufacturer's control department periodically tests samples of the bulbs, and when 1.25% or more are defective, they call repair technicians for service. The control department is going to take a random sample of 4400 light bulbs. Let p be the proportion of defective light bulbs in the sample assuming the machinery is working correctly. Answer the following. (If necessary, consult a list of formulas.) (a) Find the mean of p. (b) Find the standard deviation of p. (c) Compute an approximation for P(P ≥ 0.0125), which is the probability that, assuming the machinery is working correctly, the repair technicians will be called. Round your answer to four decimal places.arrow_forward
- Suppose that a set of ten measurements is drawn randomly. The sample consists of the set {1,1,0,15,2,3,4,0,1,3}. By inspection it is evident that the measurement x=15 appears unusually large in comparison to the rest of the measurements. Calculate the z-score equivalent for the measurement x=15 and determine if it is an outlier.arrow_forwardAt ABC College it is estimated that at most 10% of the students use public transportation to the college. Does it seem to be a valid estimate if, in a random sample of 120 students, 25 students use public transportation. (Use α = .01)arrow_forwardSuppose that 67% of voters in a state oppose concealed carry handguns. Repeated random samples of 400 voters were collected. Use the Empirical Rule to find the interval in which the sample proportion of opponents should fall 95% of the time. Select one: A. (64.6%,69.4%)(64.6%,69.4%) B. (63.8%,70.2%)(63.8%,70.2%) C. (60.7%,73.3%)(60.7%,73.3%) D. (61.5%,72.5%)(61.5%,72.5%) E. None of the abovearrow_forward
- A transect is an archaeological study area that is mile wide and 1 mile long. A site in a transect is the location of a significant archaeological find. Let x represent the number of sites per transect. In a section of Chaco Canyon, a large number of transects showed that x has a population variance . In a different section of Chaco Canyon, a random sample of 23 transects gave a sample variance for the number of sites per transect. Use an to test the claim that the variance in the new section is greater than 36.4. What is the level of significance? 90% 1% 5% 95% 10%arrow_forwardThe single sample z test may be used to determine: a)the variability in the sample b)if a sample mean is different from a known population mean c)if two population means are different d)the variability in the population of sample meansarrow_forward6% of all statistics classes require a statistical calculator and 25% require the use of a computer that has statistical software. Of the classes that require a statistical calculator, 13% also require the use of a computer. If a statistics course is selected at random find: (round to 4 decimal places where possible) a. P(Statistical Calculator) = Correct b. P(Statistical Software) = Correct c. P(Require a Statistical Calculator and Statistical Software) = Incorrect d. P(Require a Statistical Calculator GIVEN Require Statistical Software) =arrow_forward
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman





