According to Quantcast analytics of CrossFit.com, 59% of CrossFitters have children. Suppose we take a random sample of 40 Crossfitters and find the sample proportion (p) that have children. We repeat this process many times. (a) What do you expect the mean of the p's to be? (b) What do you expect the standard deviation of the p's to be?

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Q: . What is the probability that the student will get into a college whose entrance score is 550?

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A: Standard Deviation : The standard deviation(SD) measures the amount of variability, or dispersion…

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Q: What is the standard deviation of a coin tossed 100 times resulting in 40 heads and 60 tails

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Q: rcentage of fake followers was 13.3 with a standard deviation of 2.

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A: Given Information:

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A: Given Data: μ=72σ=12x=70n=50   H0: μ≥72 HA: μ<72   Under H0: x-μσ/n~ N(0,1)

Q: Suppose the scores of students on an exam are normally distributed with a mean of 458 and a standard…

A: Using empirical rule of probabilityfor normal distribution.which is  68% data cover by μ±σ 95%…

Q: The variance of a sample of 99 observations equals 81. The standard deviation of the sample equals?

A: From the provided information, The sample variance of 99 observations (s2) = 81

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A: Binomial distribution:A random variable Y denoting the number of successes in n trials for…

Q: According to one source, the average yearly cost to house a prisoner in the United States in a…

A: State the hypotheses.

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A: Standard deviation is the square root of variance

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A: The random variable systolic blood pressure follows normal distribution. The population mean is 115…

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A: Since the population is huge, so we can assume normal distribution in this scenario.  Let,…

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A: Given mean = 80 standard deviation, σ = 9 sample size, n = 100

Q: graduate student is performing a study on a new anti-anxiety drug. The drug is supposed to reduce…

A: The null and alternative hypotheses are:   H₀: μanti-anxiety druganti-anxiety drug = μ₀   H₁:…

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A: Mean = 75 Standard deviation = 15 Sample size = 9

Q: The average weekly income of a U.S. student worker is $200 with a standard deviation of 50. If a…

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Q: Loretta, who turns  91  this year, has heard that the mean systolic blood pressure among the elderly…

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Q: due to the increasing price of apartments each year, houston chronicle reported that rent of 1 bed 1…

A: Given that  μ=1200σ=500n=20 Consider, the probability that the price is more than 1100 is,…

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Q: What is the z-score for this raw score?

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Q: A recent study found that 69% of all adults over 50 wear sunglasses for driving. In a random sample…

A: Formula : Mean = np Standard Deviation  :

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Q: The mean cost of a five pound bag of shrimp is 50 dollars with a standard deviation of 6 dollars.…

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Q: A published study says that 95 percent of American children are vaccinated against measles, with a…

A: A t-test is used to determine the test if there is any significance difference between two mean…

Q: A maths class has 100 members. If there is a 15% absentee rate per class meeting , find the standard…

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Q: In order to be accepted into a certain top university, applicants must score within the top 5% on…

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Q: According to a recent report from the U.S. National Center for Health Statistics, females between 25…

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Q: if an average score of exams was 74 points for 24 students  the 25th student got 64 points whats…

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Q: lower

A: Given Mean = $ 92,300 Standard deviation = $ 32,000 (e) Standard deviation for n = 100 Standard…

Q: A history class has 75 members.  If there is a 12% absentee rate per class meeting , find the…

A: Given data  P(absent) = p = 0.12  So q= 1-p = 0.88 Sample size (n)= 75 X = no.  of student absent We…

Q: What is the standard deviation of a sample of 120 observations, if the variance of the sample 2.56?

A: It is given that the variance of the sample is 2.56.

Q: Loretta, who turns 91 this year, has heard that the mean systolic blood pressure among the elderly…

A: Given: μ = 115 x¯ = 133 s = 23 ∝ = 0.05 n = 10 The test hypothesis are, H0: μ = 115 H1: μ > 115.…

Q: The variance of a sample of 81 observations equals 64. what is  standard deviation of the sample ?

A: Given data ,no of samples n=81Variance σ2=64Std. deviation σ= ?

Q: In most cases, if you have the variance, how do you compute standard deviation?

A: We have the variance, how do you compute standard deviation.  We use here the formula of variance to…

Q: Suppose you could take all samples of size 77 from a population with a mean of 12 and a standard…

A: Given data, Mean μ=12 sd      σ=3.2 n=77 standard deviation of the sample means σx=?

Q: When interpreting a standard deviation how do I know whether its an empirical rule or Chebychev? The…

A: Empirical Rule : It states about the spread of the data in a normal distribution when mean and…

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A: