A random sample 100 students is selected from a class. Their average monthly income is $510 with a standard deviation of $52. Using a significance level of .01, test the null hypothesis that µ > $525.
Q: Manager claims average sales for her shop is $1800 a day during winter months. 10 winter days…
A:
Q: A study was done using a treatment group and a placebo group. The results are shown in the table.…
A:
Q: According to one study, the average hours of sleep on a weeknight for men was 6.9 hours with a…
A:
Q: The first answer is B. What is the test statistic
A:
Q: Es On their website, a property management company states that the mean monthly rent for apartments…
A: As per bartleby guideline expert have to answer first three subparts only dear student please upload…
Q: 4. Felician University uses hundreds of fluorescent light bulbs each year. The brand of bulb it…
A: The mean lifetime of current brand that it uses is of 900 hours. The mean and standard deviation of…
Q: A radio station claims that the amount of advertising per hour of broadcast time has an average of…
A:
Q: dult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the…
A: Given: μ=69.0σ=2.8X=59.2
Q: (a) The sampling distribution of x is (Type exact answers, using radicals (b) P(x- (Round to four…
A:
Q: Please show solution and explain. Researchers report in the AHA journal Hypertension that people…
A: We have given thatMean(µ) = 8Sample size (n) = 225Sample mean (x̅) = 8.5Standard deviations (s) =…
Q: Describe the distribution of sample means (i.e., shape, measure of central tendency and variability)…
A:
Q: A senior high school student is concerned about attending college because she heard that many…
A: The mean difference between the one sample and the population mean is calculated using the t test.…
Q: In a random sample of 8 cell phones, the mean full retail price was $521.70 and the standard…
A: A random sample of 8 cell phones, the mean full retail price was $521.70 and the standard…
Q: A researcher claims that felons convicted of tax fraud spend less than 18 months in jail, on…
A: The given sample size is 10, sample mean is 13.8, sample standard deviation is 3.3, and population…
Q: Words were displayed on a computer screen with background colors of red and blue. Results from…
A: For the given data Perform F test ratio of variances
Q: Suppose that an advertisement claims the average weight loss for someone on a new fad diet is 15…
A: Given, Sample size = 18 Sample mean = 15.83 Population standard deviation = 4 Under the claim, the…
Q: A researcher wants to test the average time it takes to solve a puzzle. They randomly sample 50…
A: Given: Sample size n=50 Sample mean x¯=8 Sample standard deviation s=2 Significance level α=0.05
Q: A sample of assistant professors on the business faculty at state-supported institutions in Ohio…
A: It is given that the mean is 72000 and the standard deviation is 3000.
Q: A sample of university students has an average GPA of 2.78 with a standard deviation of 0.45. What…
A: We have given that, Let X be the GPA scores from normal distribution with average or mean (μ) =…
Q: college entrance exam company determined that a score of 24 on the mathematics portion of the exam…
A: Given data: The sample size is n=250. The sample mean is x¯=24.4. The sample…
Q: A random sample of 36 cans of soda is obtained and the contents are measured. The sample mean is…
A: Given Population mean μ=12, n=36, sample mean x̄=12.05, s=0.11
Q: The population information about the number of motor vehicle accidents a person will be involved in…
A: The summary of statistics is, M= 2.5,s=1.3,n=50,μ=3.2 The value of test statistic is, Thus, the…
Q: mean of $5.02 and a standard deviation of $0.09. Using the Empirical rule, find the range in which…
A: Given data: Mean and standard deviation of the hourly wages of employees is: μ=$5.02σ=$0.09 The…
Q: A medical researcher administers a new medication to a random sample of 70 flu sufferers, and she…
A: From the provided information, The degree of freedom = n1 + n2 – 2 = 70 + 50 – 2 = 118 As, the…
Q: The mean value of land and buildings per acre from a sample of farms is $1600, with a standard…
A: According to the empirical rule,
Q: Peter collects data on the music scores of 200 randomly selected concertos. The sample mean of this…
A: It is given that the mean is 85,252 and the standard deviation is 8,413.
Q: A 2003 study found that Americans exercised a mean of 115 minutes per week. A more recent study…
A: Given information: A study in 2003 it was found that Americans exercises a mean of 115 minutes per…
Q: Assume that credit card FICO scores are normally distributed. A sample of 18 individuals was taken…
A: Given: Sample size (n) = 18 Sample mean (x̄) = 660.3 Sample standard deviation (s) = 95.9 The level…
Q: Light at Night and Weight Gain A study found that mice exposed to light at night gained…
A: Obtain the 90% confidence interval for the difference between two means. The 90% confidence interval…
Q: During an economic crisis, the average value of homes in a community of 36 homes lost $9347 with a…
A: Given information Hypothesized mean µ = $8880 Sample size (n) = 36 Mean x̅ = $9347 Standard…
Q: Significance Test for u 1. According to the AAA Foundation for Traffic Safety's American Driving…
A: Given: Random Sample of drivers selected sample size n=75 Mean time behind the wheel for the sample…
Q: Assume that adults have IQ scores that are normally distributed with a mean of 100.3 and a standard…
A: Assume that adults have IQ scores that are normally distributed with a mean of 100.3 and a standard…
Q: The average starting salary of students who graduated from colleges of Business in 2009 was $48,400.…
A:
Q: The mean value of land and buildings per acre from a sample of farms is $1800, with a standard…
A: Solution: Let X be the value of land and buildings per acre. From the given information, X follows…
Q: Scores on an IQ test are normally distributed. A sample of 25 IQ scores had standard deviation s=…
A: The question is about confidence interval Given : Sample size of IQ scores ( n ) = 25 Sample std.…
Q: sample of university students has an average GPA of 2.78 with a standard deviation of 0.45. What is…
A: We have given that, Let X be the GPA score from normal distribution with average or mean (μ) = 2.78…
Q: Researchers at a medical center studied the amount of caffeine, in milligrams (mg), contained in a…
A: Given x=159.88 and s = 36.72; n=40 Confidence interval =x±tαsn =…
Q: A researcher claims that the amounts of acetaminophen in a certain brand of cold tablets have a mean…
A: Given: n = 29 x¯ = 597.9 s = 3.8 α = 0.01
Q: (a)State the hypotheses and identify the claim with the correct hypothesis. (b)Find the critical…
A: Given that Population Standard Deviation = 3.2 Sample size = 42 Note : According to bartleby…
Q: The average waiting time in a doctor’s office varies. The standard deviation of waiting times in a…
A:
Q: The average life of light bulbs produced by SABA Electric Co. is expected to be normally distributed…
A: The average life of light bulbs produced by SABA Electric Co. is expected to be normally distributed…
Q: Astudy was done on body temperatures of men and women. The results are shown in the table. Assume…
A:
Q: Scores on an IQ test are normally distributed. A sample of 18 IQ scores had standard deviation s =…
A: Confidence interval: The (1-α) % confidence interval for population variance is given by:
Q: According to a research study, college students spent 24.2 hours doing homework per week last year,…
A: According to a research study, college students spent 24.2 hours doing homework per week last year,…
Q: One-Way Airfares The average one-way airfare from Pittsburgh to Washington D.C. is $236. A random…
A: According to the provided information, The hypothesis can be defined as:
Q: Test the claim that a certain x-ray machine gives radiation dosages with a mean below 5.00…
A: Givensample size(n)=28Mean(x)=4.16standard deviation(s)=1.91α=0.01
A random sample 100 students is selected from a class. Their average monthly income is $510 with a standard deviation of $52. Using a significance level of .01, test the null hypothesis that µ > $525.
Step by step
Solved in 4 steps with 4 images
- On the PSAT test taken by about 1.5 million high school juniors each year, the mean score on the reading portion of the test was 46.9, with a standard deviation of 10.9. The scores are normally distributed. If a student needed a score on this portion of the test that put them in the top 5% of scores nationally to qualify for a particular scholarship, what is the minimum score they must achieve?A researcher wonders whether the recession has changed variability in family size in his city. Before the recession, the mean was 3.7 and the standard deviation was 1.76. The researcher randomly selects 41 families from a population that is normally distributed. His sample has a mean of 3.1 and a standard deviation of 1.45. Test the claim that the standard deviation in size has changed at the αα=.05 significance level.Dr. Graham is interested in determining if middle-aged adults use text messaging more or less frequently than the general population. Dr. Graham collects information on text messaging from a random sample of 50 adults ages 25 to 44. Dr. Graham finds that these individuals send or receive an average of 68 text messages per day. Using the population mean (and standard deviation) of 41.5 texts per day (34 texts per day), determine whether adults in this age group use text messaging more than the general public.
- The quality-control manager at a compact fluorescent light bulb (CFL) factory needs to determine whether the mean life of a large shipment of CFLs is equal to 7,508 hours. The population standard deviation is 840 hours. A random sample of 49 light bulbs indicates a sample mean life of 7,328 hours. Let μ be the population mean. Determine the null hypothesis, H0, and the alternative hypothesis, H1.A random sample of 50 gas stations in Cook County, Illinois, resulted in a mean price per gallon of $2.60 and a standard deviation of $0.07. State the Empirical Rule. A histogram of the data indicates that the data follow a bell-shaped distribution. Use the Empirical Rule to determine the percentage of gas stations that have prices within three standard deviations of the mean. Determine the percentage of gas stations that have prices between $2.46 and $2.74, according to the Empirical Rule. Explain your calculations. Would a gas price of $2.99 be considered unusual in the statistical sense? Why or why not?According to the Statistical Abstract of the United States, the mean family size in 2010 was 3.14 persons. Suppose a random sample of 225 families taken this year yields a sample mean size of 3.05 persons, and suppose we assume the population standard deviation of family sizes is o = 1 person. Using a 5% significance level, test the hypothesis that the mean family size has decreased since 2010. Perform your hypothesis test, and select the best interpretation of your results from the choices below. Select one: O a. At the 5% level of significance the data are statistically significant. We cannot determine the average family size has decreased since 2010. O b. At the 5% level of significance the data are statisticall significant. We can determine the average family size has decreased since 2010. O c. At the 5% level of significance the data is not statistically significant. We cannot conclude the average family size has decreased since 2010. O d. At the 5% level of significance the data…
- Insurance Company A claims that its customers pay less for car insurance, on average, than customers of its competitor, Company B. You wonder if this is true, so you decide to compare the average monthly costs of similar insurance policies from the two companies. For a random sample of 1313 people who buy insurance from Company A, the mean cost is $151$151 per month with a standard deviation of $16$16. For 99 randomly selected customers of Company B, you find that they pay a mean of $158$158 per month with a standard deviation of $19$19. Assume that both populations are approximately normal and that the population variances are equal to test Company A’s claim at the 0.050.05 level of significance. Let customers of Company A be Population 1 and let customers of Company B be Population 2. Step 2 of 3: Compute the value of the test statistic. Round your answer to three decimal places.A manufacturer advertises that the average life of batteries produced by his firm is at least 12 months. The consumer board disagrees, and claims that the average life of the batteries is less than 12 months. The consumer board test a random sample of 9 batteries and find that the mean life is 10.6 months with a standard deviation of 2. The consumer board's alternative hypothesis is: A. The average life of the population of batteries is 12 months. B. The average life of the population of batteries is less than 12 months. C. The average life of the population of batteries is more than 12 months. D. The average life of the population of batteries is at least 12 monthsThe manufacturer of 'Road King' tyres claim that their tyres last an average of 70,000km or more. The Consumer Board suspects that this claim may be false (they have received some complaints) and decide to test the manufacturer's claim. The Consumer Board took a sample of size 500 from the population. They ran the…A large financial company employs a human resources mamanger who is in charge of employe benefits. The manger wishes to estimate the average dental expenses per employee for the company. She selects a random sample of 60 employee records for the past year and determines that the sample mean of $492. Moreover, it is known from past studies that the population standard deviation for annual dental expenses is $74. Use this data to calculate a 95% cofidence interval for the mean expenses of all employees.
- A Two-Sample Hypothesis TestThe mean number of English courses taken in a two-year time period by male and female college students is believed to be about the same. An experiment is conducted and data are collected from 29 males and 16 females. The males took an average of three English courses with a standard deviation of 0.8. The females took an average of four English courses with a standard deviation of 1.0. Are the means statistically the same? (Assume a 5% level of significance.)Useful tools:Normal Distribution Calculatort-Distribution Calculator 1. Which of the following null and alternative hypotheses match this scenario? A---H0:Δμ=0H0:Δμ=0Ha:Δμ≠0Ha:Δμ≠0 B---H0:Δμ≠0H0:Δμ≠0Ha:Δμ=0Ha:Δμ=0 C---H0:Δμ=0H0:Δμ=0Ha:Δμ>0 2. Which type of test should be applied? A---The alternative hypothesis indicates a right-tailed test. B---The alternative hypothesis indicates a left-tailed test. C---The alternative hypothesis indicates a two-tailed test. 3. Which type of distribution should be…24I wanted to do a market research study estimating the average hourly wage earned by childcare workers in the bay area. How large does my sample need to be in order to have a margin of error that is less than $0.50 with a 95% confidence in the result. Assume that the standard deviation of the wages is $2 per hour.