A shoemaker claims his best product has an average lifespan of exactly 14 years. A skeptical customer asks for evidence (data) that might be used to evaluate this claim. The customer was provided data collected from a random sample of 45 people who used the product. Using the data, an average product lifespan of 15 years and a standard deviation of 6 years was calculated. Select the 95%, confidence interval for the true mean lifespan of this product.   a) [14.739, 15.261] b) [13.247, 16.753] c) [12.317, 17.683] d) [12.247, 15.753] e) [-1.7531, 1.7531] f) None of the above

Q: The mean number of sick days an employee takes per year is believed to be about 10. Members of a…

A: Given Information: Sample size n=8 11, 4, 14, 4, 11, 9, 7, 9 Significance level α=0.05 X is the…

Q: a. Write out the null and alternative hypotheses for our test in words or in symbols. b. Use the…

A:

Q: A doctor compares three treatments for arthritis. He uses three samples, each of size six, in the…

A: We have given that  Three treatment  and each treatment having six size .

Q: The following sample was obtained from the population. 13,7,6,12,0,4 b) Compute the sample…

A:

Q: What does the null hypothesis assume for two indepdent samples t test? There is no difference…

A:

Q: 12. The mean life span of caterpillars before becoming butterflies is 4.75 months with a population…

A: 12. Let μ be the population mean life span of caterpillars before becoming butterflies. The test is…

Q: A computer magazine is evaluating the charge life of a new notebook computer battery.  As part of…

A: The type II error is the probability of fail to reject the null hypothesis when alternative…

Q: A study is done to determine if students in the California state university system take longer to…

A: " Since you have posted a question with multiple sub-parts, we will solve the first three subparts…

Q: For a 4-units class like Statistics, students should spend average of 12 hours studying for the…

A: Solution: a. Let X be the total study hours per week. From the given information, X follows normal…

Q: Q. No. 3. A. Forty-two items are randomly selected from a population of 500 items. The sample mean…

A: Given, sample size= 42 Sample mean=x¯ = 40 Sample sd= s =9 Let, population mean be μ

Q: A study was conducted on the life of Duracell batteries and on the life of Energizer batteries. The…

A: Note: According to bartleby experts question answers guidelines an expert can solve only first three…

Q: Determine the decision rule for rejecting the null hypothesis H0H0. Round the numerical portion of…

A: Given that  Sample sizes n1=70      , n2=85       Sample means X̄1=8.84     , X̄2=9.05      ?1 =0.30…

Q: comparison betw species: Biologists comparing the gestation perod of newly discovered species of…

A: The provided information is For Ax¯1=11s1=3.6x¯2=15s2=3.6n1=15n2=23α=0.10 a. The null and…

Q: A comparison between species: Biologists comparing the gestation period of two newly discovered…

A:

Q: 2. Assume a researcher wants to compare the mean Alanine Aminotransferase (ALT) levels in two…

A: Let x1-bar is the mean ALT and s1 is the standard deviation of the individuals who drink alcohol…

Q: For a 4-unit class like Statistics, students should spend average of 12 hours studying for the…

A: Given data, Mean is 14 sd is 3.5 n=28 By empirical rule 68% of the data lies within one standard…

Q: For a 4-unit class like Statistics, students should spend average of 12 hours studying for the…

A: Given data,n=22x=13s=3.1   By empirical rule 68% of the data lies within one standard deviations of…

Q: For a 4-units class like Statistics, students should spend average of 12 hours studying for the…

A:

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: Find a 95% confidence interval on the difference in mean life. Find the following: a. Pooled…

A:

Q: A random sample of 11 adults is obtained, and each person’s red blood cell count (in cells per…

A: Given: Hypothesized mean μ=4.7 X= The red blood cell count (in cells per microliter) Sample mean…

Q: A comparison between species: Biologists comparing the gestation period of two newly discovered…

A: There are two samples of species which are named as species A and species B. The species follows…

Q: A statistics teacher taught a large introductory statistics class, with 500 students having enrolled…

A: Given, The null and alternative hypothesis. and population mean and standard deviation. also Sample…

Q: Company ABC's customer retentions per site are normally distributed with a standard deviation of 21…

A: Solution: Let X be the Company ABC’s customer retentions per site. From the given information, X…

Q: April took a sample of 10 statistics students from MCC and found the mean of th scores on their…

A: a.) Construct a 90% confidence interval for MCC statistics students mean score on the second exam.…

Q: The following random sample was selected from a normal distribution: 8, 10, 7, 9, 13, 7. The formula…

A:

Q: The brain volumes ​(cm3​) of 20 brains have a mean of 1143.3 cm3 and a standard deviation of 129.9…

A: Introduction: It is required to find the limits separating the significantly lower and higher…

Q: Which of the following statements is correct? Select one: a. If there is less variability within the…

A: Introduction: It is required to identify each statement as true or false

Q: In an experimental study of the longevity of Drosophila melanogaster (fruit fly) 70 male adults and…

A: Solution: 1. State the hypotheses. Null hypothesis: That is, the male Drosophila not has a greater…

Q: In a test of the Atkins weight loss program, 27 individuals participated in a randomized trial with…

A: Since, you have asked multiple question, we will solve the first question for you. If you want any…

Q: If the proportion differs from 30%, then the lab will modify a proposed enlargement of its…

A:

Q: Consider two populations in the same state. Both populations are the same size (22,000). Population…

A: The following solution is provided below :

Q: A sample of 12 adults was chosen to determine how many books adults read each year. The mean number…

A: The sample size  n=12 The sample mean x¯=10.5 The sample standard deviation  s=2.3 The confidence…

Q: Given the following GPA for 4 students: 2, 3, 3, 4. Age of students are: 10, 11, 12, 15. There are…

A: Given Given the following GPA for 4 students: 2, 3, 3, 4. Age of students are: 10, 11,12, 15. There…

Q: For a study of two independent samples: Sample 1: mean = 18.1, standard deviation = 2.5, sample size…

A: Given: For Sample 1: Mean, x1 =18.1 Standard deviation, s1=2.5 Sample size, n1=30 For Sample 2:…

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: From a sample of 18 tellers operating in different branches of a bank, it turned out that during a…

A: From the provided information, Sample size (n) = 18 Sample mean (x̄) = 60 Sample variance (s2) = 81

Q: Suppose a study reported that the average persin watched 3.37 hours of television per day. a random…

A:

Q: Justine is an analyst for a sleep study center. She believes that the average adult in a certain…

A:

Q: A dietician wishes to see if a person’s cholesterol level will change if the diet is supplemented by…

A: Let μd denotes the mean difference (Before - After) between the cholesterol level. The test is that…

Q: Use the following scenario to answer the next 6 questions. An engineer has designed a valve that…

A: Given: Sample size (n) = 30 Sample mean (x̅) = 4.8 Sample standard deviation (s) = 1 Level of…

Q: The breaking strengths of cables produced by a certain manufacturer have a mean, µ, of 1875 pounds,…

A: (a)   State the hypotheses.

Q: A hypertension trial is mounted, and 12 participants are randomly assigned to receive either a new…

A: The type of test is two tailed test The appropriate test is two sample t-test using equal variances

Q: The coach of a very popular men’s basketball team claims that the average distance the fans travel…

A: For the given data Perform t test for one mean