5. Assume that the helium porosity (in percentage) of coal sam- ples taken from any particular seam is normally distributed with true standard deviation .75. a. Compute a 95% CI for the true average porosity of a cer- tain seam if the average porosity for 20 specimens from the seam was 4.85. b. Compute a 98% CI for true average porosity of another seam based on 16 specimens with a sample average poros- ity of 4.56. c. How large a sample size is necessary if the width of the 95% interval is to be .40? d. What sample size is necessary to estimate true average porosity to within .2 with 99% confidence?

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A:

Q: A hospital orders surgical supplies using a fixed order interval system. Suppose that just prior to…

A: To find : The expected demand during the order interval and lead time.

Q: In Country A, the population mean height for 10-year-old girls is 53.6 inches with a standard…

A: Null hypothesis: Null hypothesis is the statement about parameter of population. Alternative…

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A: Given that

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A: we have given that  n1=35 ,n2=35 xbar1=44 ,xbar2=46 ,sigma1=4.9, sigma2=4.7  and alpha =0.10 Note :…

Q: 4. Suppose that in the past years the average price per square foot for warehouses in Subic has been…

A: One sample t-test: The one -sample t -test is used to determine whether the mean of sample differs…

Q: The town of KnowWearSpatial, U.S.A. operates a rubbish waste disposal facility that is overloaded if…

A: It is given that the samples of 4751 households have weights that are normally distributed with a…

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A: GivenMake Ax1^=42s1=4.9n1=35Make Bx2^=43s2=4.6n2=35α=0.10

Q: 2) Collect your own random sample of 6 sodas from a normal distribution with a mean of 12 fluid…

A: From the given information, a random sample of 6 sodas from a normal distribution with a mean of 12…

Q: A particular manufacturing design requires a shaft with a diameter of 21.000 ​mm, but shafts with…

A: Note: Hi there! Thank you for posting the question. As there are multiple sub parts, according to…

Q: A particular manufacturing design requires a shaft with a diameter of 21 000 mm, but shafts with…

A: The mean is 21.002 mm and the standard deviation is 0.006 mm.

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of​ automobiles, a…

A: we have given that  n1=35 ,n2=35 ,xbar =43,  xbar =44 ,sigma1=4.7 and sigma2=4.5   Note : according…

Q: Assume the samples are random and independent and the populations are normally distributed. A marine…

A: Given problem is :   Assume the samples are random and independent and the populations are…

Q: A manufacturer claims that the average lifetime of his lightbulb is 3 years or 36 months. The…

A: The one-sample z-test is used to test whether the mean of a population is greater than, less than,…

Q: It is known from a previous study that in a factory producing steel ropes, the ropes drawn by ropes…

A: The standard deviation is 45 and the standard error is 12.

Q: 9. The Taylor Steel Company wants to determine whether there is a significant difference in…

A: Solution: Given information: n1= 130 Sample size of day shiftn2= 120 Sample size of night shiftx1=…

Q: A particular manufacturing design requires a shaft with a diameter of 21.000 mm, but shafts with…

A: Press 2ND and VARSChoose normalcdf

Q: Nationally, social workers average 10.2 years of experience. In a random sample, 203 social workers…

A:

Q: Suppose that 100,000 recent grads have starting salaries which are normally distributed with a mean…

A: Given that  μ=120,000σ=20,000 b) Consider the probability that the salary above $131,200 is,…

Q: A researcher claims that the mean of the salaries of elementary school teachers is greater than the…

A: Given: The descriptive statistics given is as follows

Q: A group of apples from a particular grower were found to have diameters with a mean of 69.0 mm and a…

A:

Q: Suppose that the manager of a construction suupplyu house determined from historical records that…

A: a. The stock out risk is assumed to be no more than 2% For confidence level of 1-0.02=0.98, the…

Q: n a recent survey of nurses in Region X, it was found out that the average monthly net income of…

A: Given : Sample size (n) =158 Sample mean (X¯) = 9568.40 Population standard deviation (σ) = 1563.42

Q: A paper filter manufacturer supplies filters of nominal grammage equal to 455 g/m?. A customer…

A:

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A: Other parts are not provided by you. Still I have tried to provide you detailed solution

Q: A consumer group claims that the mean annual consumption of banana by a person in the Philippines is…

A:

Q: Assume that the weights of quarters are normally disturbanced with a mean of 5.67g and a standard…

A: Let, X= weights of quarters Given that X follows a normal distribution with mean= 5.67 and standard…

Q: The U.S. Federal Reserve System publishes data on family income based on its Survey of Consumer…

A: Given that the mean pre-tax family income is $85,200.   Here 60% of the pre-tax family incomes when…

Q: For a sample of 106 transformers built for heavy industry, the mean and standard deviation of the…

A: The mean and standard deviation of the number of sags per weeks are 363 and 33, respectively.

Q: Suppose a paint manufacturer has a daily production, X, that is normally distributed with a mean of…

A: Given: X~N(μ,σ)μ=100000σ=10000

Q: 1. Assume that the average yearly pay of all teachers in the Philippines follows a normal…

A: Here all are normally distributed

Q: The U.S. Federal Reserve System publishes data on family income based on its Survey of Consumer…

A:

Q: Suppose in a city of 100,000 residents, a survey was conducted with size of 1650. If Forty-two…

A: GivenThe sample size = 1650The percentage of population opposes the new taxes for the geothermal…

Q: In Country A, the population mean height for 10-year-old girls is 54.9 inches with a standard…

A: The following information has been provided: The population mean is μ=54.9. The population standard…

Q: Suppose that the annual household income in a small Midwestern community is normally distributed…

A: Solution: Let X be the annual household income in a small Midwestern community is normally…

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A:

Q: 2. A manufacturer of mugs packages them in boxes of 100.lt is shown that, on the average, mugs weigh…

A: Solution

Q: If the average price of a new single family home is $246,300 with a standard deviation of $15,000,…

A: Given , Mean (u) =246300 Standard deviation =15000

Q: An article reported that for a sample of 45 kitchens with gas cooking appliances monitored during a…

A: Confidence Interval - In interval estimation, confidence interval gives amount of error that can be…

Q: Assume that military aircraft use ejection seats designed for men weighing between 146 to 209…

A: The Z-score of a random variable X is defined as follows: Z = (X – µ)/σ. Here, µ and σ are the mean…

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A: There are two independent samples which are make A and make B. We have to test whether the mean…

Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

A: Given,X1=42, σ1=4.7, n1=35X2=45, σ2=4.4 , n2=35and level of significance α=0.10

Q: 2. The owner of a factory that sells a particular bottled fruit juice claims that the average…

A: Given: population mean(μ)=250sample size(n)=100sample mean (x¯)=248standard deviation(σ)=5

Q: Suppose that water usages in American showers are normally distributed, with an average shower using…

A: Given: mean = 17.1, SD = 3.5

Q: 3- At a computer manufacturing company, the actual size of a particular type of computer chips is…

A: We have to find required sample mean.

Q: Assume that the helium porosity (in percentage) of coal sam- ples taken from any particular seam is…

A: Note: Hi there! Thank you for posting the question. As there are multiple sub parts, according to…

Q: The town of KnowWearSpatial, U.S.A. operates a rubbish waste disposal facility that is overloaded if…

A:

Q: 2.) A ski gondola in Vail, Colorado that carries skiers up a mountain bears a plaque stating that…

A: n=12, maximum weight = 2004 mean = 188.6  std.dev = 38.9

Q: According to the Annual survey of drugs expenditure in country X, the annual expenditure…

A: Let X be the random variable such that drugs expenditure in-country  x̅: Sample mean of drugs…

Q: We want to test whether the mean fluoride levels in water fountains is worse in A or B. In order to…

A: From the given information, the sample size n1 is 49, the sample size n2 is 36. A has a sample…