not be true. A simple random sample of 80 hospitals at a moment during the day gives a mean noise level of 47 db. Assume that the standard deviation of noise level for all hospitals is really 9 db. All answers to two places after the decimal. (g) How many hospitals must we examine to have 95% confidence that we have the margin of error to within 0.25 db? (h) How many hospitals must we examine to have 99.9% confidence that we have the margin of error to within 0.25 db?

Q: A distribution of exam scores has a mean of μ = 42. If your score is X = 46, which standard…

A: we have to find which sd will give better score.

Q: A population of scores has μ = 25 and σ = 1. If 3 points are added to every score in the population,…

A: From the given information, Consider , X be the random variable which denotes the scores. Ex=μ=28σ=1…

Q: The distribution of scores on a standardized test is approximately Normal with a standard deviation…

A: According to the provided information, Mean (x̅) = 76.8 Standard deviation (σ) = 22 Sample size (n)…

Q: (b) Find the 1oth percentile of x. Round the answer to at least two decimal places. The 10t…

A: Given that.   X~N( μ , ?^2 )   μ= 31    , ?=6  ,n=60   Z-score =( x - μ )/?

Q: Co 1. The average age of attendees at an amusement park is 45.8 years old. 50 randomly selected…

A:

Q: Use the formula to find the standard error of the distribution of differences in sample means,…

A:

Q: Scores on a test have a mean of 86 and a standard deviation of 13. Jerrica has a score of 94.…

A:

Q: Suppose that you know that the normal body temperature of adults is normally distributed with a…

A: When the population standard deviation is known and the population is normally distributed then the…

Q: On an exam with a mean of M = 98, you obtain a score of  X= 90. Would you prefer a standard…

A: It is not known whether the distribution of the score is symmetric or not. Hence ,we cant use…

Q: We want to estimate the true pH of a test tube of solution. The pH meter is known to have a standard…

A:

Q: The scores on a mathematics exam have a mean of 71and a standard deviation of 8. Find the x-value…

A: Let X denote the scores on a mathematics exam and it follows normal distribution with mean of…

Q: A set of 340 examination scores exhibiting a bell-shaped relative frequency distribution has a mean…

A:

Q: To estimate the mean height μ of male students on your campus, you will measure an SRS of students.…

A: From the provided information, The height of young men are approximately normal with standard…

Q: 2. The heights are measured for a simple random sample of 9 supermodels. They have a mean of T =…

A:

Q: A nutritionist claims that the mean tuna consumption by a person is 3.1 pounds per year. A sample…

A: Solution: Let X be the tuna consumption by a person. From the given information, n=90, x-bar=2.9 and…

Q: you want to obtain a sample to estimate a population mean. based on previous evidence, you believe…

A:

Q: Problem #2: An apple grower selects a random sample of 35 apples from this year's crop. The mean and…

A: The sample size, i..e, the sampled number of apples, n=35.The sample mean and standard deviation of…

Q: The table available below shows the weights (in pounds) for a sample of vacuum cleaners. The weights…

A: Bagged uprightBagless uprightTop canister212025222226231823191927201728192222

Q: Suppose a randomly selected sample of n = 36 men has a mean foot length of x = 27.5 cm, and the…

A: Given data: Sample size = 36 Mean = 27.5 cm Sample standard deviation = 2 cm

Q: An SRS of 350 high school seniors gained an average of x = 45 points in their second attempt at the…

A:

Q: Suppose that the heights of college women follow a normal distribution with a mean 65 inches and a…

A: Let X represent the heights of college women Mean=65 Standard deviation=2.5   X~ Normal (65, 6.25)…

Q: The variance of a population is 8. the size of the sample collected from a population is 328 What is…

A: Answer: From the given data, Variance (σ2) = 8 Sample size(n) = 328

Q: Suppose a population is known to be normally distributed with a mean, μ, equal to 116 and a standard…

A:

Q: experience shows that consumers may patronize restaurants as far as about 3 km. How large a sample…

A:

Q: It takes an average of 12.5 minutes for blood to begin clotting after an injury. An EMT wants to see…

A:

Q: A cohort of patients have lost on average 23 pounds and the standard deviation of the sample is 1.2…

A: We have been given that a cohort of patients have lost on average 23 pounds and the standard…

Q: A UCLA researcher claims that the life span of mice can be extended by as much as 25% when the…

A: Given that, Standard deviation = σ = 5.8 Margin of error = E = 2 100 (1 - α)% = 99% α = 0.01α2 =…

Q: The average birth weight for for a full term baby in Canada is 8 Ibs with a standard deviation of 1…

A: Let X denote the birth weight for a full term baby. Given that X follows N(mean = 8, SD = 1), then Z…

Q: A nutritionist claims that the mean tuna consumption by a person is 3.6 pounds per year. A sample of…

A: Given, A nutritionist claims that the mean tuna consumption by a person is 3.6 pounds per year. A…

Q: c. Find the minimum number for the upper quarter of percent of fat calories.

A: The mean is 38 and the standard deviation is 10.

Q: In a survey, the mean weight of 1005 rats was calculated to be 132 gr. The standard deviation of the…

A:

Q: Is this possible to do using the ti-84 plus calculator? (not all calculators have the same…

A:

Q: x=200,μ=225,σ=10 x=1,μ=−1,σ=2 x=0,μ=−400,σ=200 x=12,μ=21,σ=3 The x value of ? lies the greatest…

A: Given information are,Let, (a) x=200, μ=225, σ=10(b) x=1, μ=−1, σ=2(c) x=0, μ=−400, σ=200(d) x=12,…

Q: ive a life expectancy of x = 71.5 years with a standard deviation of s, = 6.6 years. A sample of 6…

A: According to guidlines we can strickly answer three subspartsRural town:Sample size Sample mean…

Q: For healthy adults, the mean pH of arterial plasma (i.e., acidity of the blood) is 7.4. A new drug…

A: The mean pH of arterial plasma (i.e., acidity of the blood) is 7.4.

Q: A manufacturer of light bulbs finds that one light bulb model has a mean life span of 1030 h with a…

A:

Q: A population of N=5 scores has a mean of µ=7. After one score is removed, the mean is found to be…

A:

Q: A California lake has been stocked with rainbow trout. These trout have an average length of 24…

A: Given Information: Mean μ=24 Standard deviation σ=3 Someone goes fishing and catches a trout that is…

Q: A nutritionist claims that the mean tuna consumption by a person is 6 pounds per year. A sample of…

A:

Q: If the variance of the water temperature in a lake is 27° how many days should the researcher select…

A: Given data,σ2=27σ=5.196E=5Z-value at 95% confidence is Zc=1.96n=?

Q: Mason earned a score of 226 on Exam A that had a mean of 250 and a standard deviation of 40. He is…

A: First find the standardised Z score and the make equivalency