An industrial designer wants to determine the average amount of time it takes an adult to assemble an “easy to assemble” toy. A sample of 16 times yielded an average time of 19.92 minutes, with a sample standard deviation of 5.73 minutes and a z value of 2.131. Assuming normality of assembly times, provide a confidence interval for the mean assembly time.

Q: In a test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with…

A: From the provided information: Sample size, n=43. Sample mean, x¯=3.4. Sample standard deviation,…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with…

A: The random variable LDL cholesterol level follows normal distribution. We have to construct 99%…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 48 subjects were treated with…

A: Given information- Sample size, n = 48 Sample mean, x-bar = 3.4 Sample standard deviation, s = 18.9…

Q: A study was performed to determine whether men and women differ in repeatability in assembling…

A: Given: n1=28n2=25s1=1.98s2=2.31α=0.02

Q: A random sample of 100 households was selected as part of a study on electricity usage, and the…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with…

A: Here we need to find a 95% confidence interval for the mean net change in LDL cholesterol after the…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 48 subjects were treated with…

A:

Q: test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with garlic…

A: Given that  Sample size n =43 Sample mean =5.7 Standard deviation =16.1

Q: In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with…

A:

Q: and after the treatment. The changes (before-after) in their levels of LDL cholesterol (in mg/dL)…

A: Given n=sample size=49, Sd=17.1,  mean difference x̄d=2.8  Level of significance ɑ=0.05

Q: In tests of a computer component, it is found that the mean time between failures is  917  hours. A…

A: Solution-: Given: μ0=917,σ=57,x¯=963,n=25,α=0.01 We want to perform a hypothesis test to determine…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 47 subjects were treated with…

A: Obtain the 90% confidence interval estimate of the mean net change in LDL cholesterol after the…

Q: A construction company was approached by a manufacturer of rechargeable batteries for cordless…

A: Null and alternative hypotheses: The investigator is interested to test whether the average life of…

Q: random sample of 26 checking accounts at a bank showed an average daily balance of $300 and a…

A: Sample size n = 26

Q: In a test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with…

A: Given Information: Sample size n=43 Sample mean x¯d=3.2 Sample standard deviation sd=17.9 Confidence…

Q: A company which produces batteries claims that the life expectancy of their batteries is at least 90…

A: Given Information: Claim: The life expectancy of batteries is at least 90 hours. Sample size n=40…

Q: A random sample of 12 chemists from Washington stats shows an average salary of $39,420 with a…

A: The sample mean one (Washington): x¯1=$39,420, sample mean two (New Mexico): x¯2=$30,215, population…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 47 subjects were treated with…

A: The random variable net change in LDL cholesterol follows normal distribution. The sample size is…

Q: Consider evidence from a random sample of 15 cars of the same model. The average gas mileage from…

A: given data  assume normal distribution with σ = 5.2sample size (n) = 15sample mean (x¯) = 26.790% ci…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 47 subjects were treated with…

A: Let d denotes the changes (before-after) in the levels of LDL cholesterol (in mg/dL) of the…

Q: The number of hours that a population sleeps daily has a normal distribution. From a random sample…

A: A confidence interval for the population mean is given by;

Q: nd a standard deviation of 18.9. Construct a 90% confidence interval estimate of the mean net change…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 50 subjects were treated with…

A: Given n=50 Mean=5.5 Standard deviations=17.9 Alpha=0.01

Q: To determine the average number of minutes it takes to manufacture one unit of a new product, an…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 48 subjects were treated with…

A: Given that x¯=5.2s=15.6n=48 Confidence level=90% Significance level=1-0.90=0.10 degrees of freedom,…

Q: In tests of a computer component, it is found that the mean time between failures is 920 hours. A…

A: Solution: Given information: n= 36 Sample size  x= 966  hours Sample mean μ=920  hours  Population…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with…

A: given data sample size (n) = 43sample mean ( x¯ ) = 4.2sample standard deviatio (s) =17.890% ci for…

Q: A paper manufacturer has a production process that operates continuously throughout an entire…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with…

A: Sample mean = x̅ = 4.5 Sample size = n = 43 Sample S.D = s = 16.8 Standard Error = s/√n  =…

Q: Construct a 95% confidence interval estimate of the mean net change in LDL cholesterol after the…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with…

A: Since population standard deviation is unknown, Use t-distribution to find t-critical value. Find…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with…

A: sample size(n)=49Mean()=3.6standard deviation(s)=17.7confidence level=90%

Q: A study of the operation of a parking garage showed that, in the past, the average parking time was…

A: The hypotheses can be constructed as: Null hypothesis: H0: µ = 220 Alternative hypothesis: H1: µ ≠…

Q: A quality control manager at a light bulb factory needs to estimate the mean life of a large…

A:

Q: A sample of 20 international students attending an urban U.S. university found that the average…

A: Suppose µ is the population mean monthly expense budget of the international students.

Q: A cheese maker sells cheese in wheels that are known to have a standard deviation of 1.9ounces. If a…

A:

Q: Suppose the population mean is known to be 42.8 minutes with a population standard deviation of 14.7…

A: It is given that  Population mean = 42.8 Population standard deviation = 14.7 Sample mean = 44.783…

Q: An ambulance service located at the edge of town is responsible for serving a large office building…

A: It is given that: For the route A:  x¯=5.9sx=1.4n1=5 For the route B, y¯=4.2sy=1.8n2=6

Q: le of 16 ten-year-old girls had a mean weight of 71.5 and a standard deviation of 12 pounds,…

A: Confidence interval: It is defined as the range that contains the value of the true population…

Q: In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 42 subjects were treated with…

A:

Q: An industrial designer wants to determine the average amount of time it takes an adult to assemble…

A:

Q: In a test of the effectiveness of garlic for lowering cholesterol, 43 subjects were treated with…

A: Obtain the 99% confidence interval estimate of the mean net change in LDL cholesterols after the…

Q: A sample of 30 randomly selected patients in a waiting room at a doctor’s office reported a mean…

A: Solution: Given information: n= 30 Sample size  x= 38.5 minutes  Sample mean σ= 1.78 minutes…

Q: A random sample of 100 households was selected as part of a study on electricity usage, and the…

A: It is an important part of statistics. It is widely used.