For a random sample of size 10 from a normal population, the mean is 12.1 and the standard deviation is 3.2. Is it reasonable to suppose that the population mean is 14.5 ? Test at 5% significance level. (Clearly state the null and alternative hypotheses And assumptions.)

Q: A random sample of 64 business students required an average of 100 minutes to complete a statistics…

A: Given that, Mean = 100 Standard deviation = 20 Sample size = 64 95% confidence level

Q: A statistics professor takes a random sample of 25 students who have taken a special statistics…

A: From the provided information, Sample size (n) = 25 Sample average (x̄) = 86 Sample standard…

Q: A researcher wants to estimate the average age of patients newly diagnosed with type II diabetes…

A: Claim: the average age of diagnosis of these patients is different from 50 years.The null and…

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 12 for the population…

A: Givenstandard deviation(σ)=12Marign of error(E)=7c=99%α=1-0.99=0.01α2=0.005zα2=z0.005=2.5758   (from…

Q: An article in the San Jose Mercury News stated that students in the California state university…

A: We have given the following information.  Hypothesized population mean = 4.5 Sample mean =5.1 Sample…

Q: The concentration of benzene was measured in units of milligrams per liter for a simple random…

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Q: A psychologist wants to estimate the variance of scores obtained by employees on a test. A random…

A: Confidence interval:A confidence interval shows the probability that a parameter will fall between a…

Q: A simple random sample of size n=15 is drawn from a population that is normally distributed. The…

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Q: What is the likelihood that a randomly selected student from a population of 500 has a grade point…

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Q: A sample of 25 observations is taken from a normal distribution with unknown mean. The sample mean…

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Q: A random sample of 100 students is taken from a larger population of students in a multi-lecture…

A: We have given that  Claim : population average differs from 67. sample size = n =100…

Q: A random sample of 100 observations produced a mean x̅ =38.5 and a standard deviation of 3.2. find a…

A: Given information Sample size(n) = 100 Sample mean x̅ =38.5 Sample standard deviation = 3.2…

Q: Suppose that the mean time for a certain car to go from 0 to 60 miles per hour was 7.6 seconds.…

A: 1). The hypotheses for the test is given below: Null hypothesis: H0: µ = 7.6. Alternative…

Q: You are doing a right-tailed hypothesis test for the mean and have to approximate the standard…

A: It is given that the test is right-tailed. Level of significance is 0.01 Degrees of freedom is 39-1=…

Q: A random sample of size 25 from a normal population has mean 47.5 and standard deviation 8.4. Does…

A: In order to test the claim that the mean of the population is 42.1, conduct a single mean comparison…

Q: A random sample of 100 students is taken from a larger population of students in a multi-lecture…

A: R command has used.

Q: A Industrial Psychology test was written. From a sample of 50 students and it was found that the…

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Q: Suppose scores on exams in Biology are normally distributed with an unknown population mean and a…

A: given data σ = 5.4n = 60 x¯ = 81find 90% ci for μ = ?

Q: We draw a random sample of size 25 from the normal population with the variance 2.4. If the sample…

A: Since we know population standard deviation, use z-distribution to find z-critical value. Find…

Q: Listed in the data table are IQ scores for a random sample of subjects with medium lead levels in…

A: Calculating sample mean and sample standard deviation for medium lead level:…

Q: The concentration of benzene was measured in units of milligrams per liter for a simple random…

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Q: The mean IQ for the entire population in any age group is known to be 100 with a standard deviation…

A: The random variable IQ follows normal distribution. The population standard deviation is 15. The…

Q: The weights, in grams, of 30 randomly selected apples from a large bin are shown below. The mean…

A: To determine if the data appears to be normally distributed, by creating a histogram

Q: A population is hypothesized to have a mean of 10. A sample of 64 results in a mean of 10.5 and…

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Q: When 40 people used the Weight Watchers dies for one year, their mean weight loss was 3.0 lb and the…

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Q: An IQ test is designed so that the mean is 100 and the standard deviation is 13 for the population…

A: We have given that,  Mean (μ) = 100,  standard deviation (σ) = 13 and confidence level = 95%  and…

Q: The test statistic is calculated to be 1.756. Using a 5% level, the conclusion would be

A: Given :  A producer of televisions claims that his product will last at least 10 years on average.…

Q: Find the 90% confidence interval for the variance and standard deviation of the ages of students at…

A: Confidence interval: The (1-α) % confidence interval for population standard deviation is given by:

Q: Assume the scores on a standardized test are known to follow a bell-shaped distribution with a mean…

A: Here,  Sample size =1250 Mean=90 Variance =9 Standard deviation =3 Empirical rule: 68% of the data…

Q: What is the smallest sample size required to provide a 95% confidence interval for a mean, if it…

A: We want to find the sample size  Given Margin of error=E=1 Standard deviation=σ=3 The critical value…

Q: The mean annual tuition and fees for a sample of 8 private colleges was $30,000 with a standard…

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