When is a t-test used instead of a z-test? a When the population deals with two samples b. When the population μ is known c. When the population standard deviation is unknown d. When the population s

Q: A researcher wants to determine if body weight is associated with the number foreign countries a…

A: ANOVA is used to test whether the mean of three or more groups are equal.Pearson's correlation is…

Q: Claim: The standard deviation of pulse rates of adult males is more than 12 BPM. For a random sample…

A: Given  Ho: σ=12 vsH1:σ>12 n=155, s=12.8 We want to find the test statistic

Q: Assume the random variable X is normally distributed, with mean u=57 and standard deviation o = 7.…

A: The random variable  X is normally distributed The population mean is 57. The population standard…

Q: can you find the mean and standard deviation?

A: Let the male data set is denoted by x, then the mean is given by the formula x¯=∑xxn. Where, the…

Q: In a​ country, the mean time served by prisoners released from prison for the first time is 31.5…

A: Mean time = 31.5Standard deviation = 16.3

Q: What if I'm told what the standard deviation is, can I find the variance? What units is standard…

A: Introduction  The questions is about standard deviations. Can we find the variance. And whate units…

Q: Contrary to popular opinion, a psychologist claims that the mean IQ score of math instructors is…

A: The provided information is  n=25x¯=120σ=30µ=100 here the parameters are known then we use…

Q: Use Z scores to compare the given values The tallest living man at one time had a height of 245cm.…

A:

Q: Assume that adults have IQ scores that are normally distributed with a mean of μ = 105 and a…

A: Let x be an IQ scorewant to find the probability that the IQ score is less than 135i.e. P(X<135)

Q: Data for two variables (for height in cm and weight in kg) are taken from 100 female and 100 male…

A: The variability is directly proportional to standard deviation. So, lower the standard deviation,…

Q: 21. What is the probability of selecting someone from the general population at random who would…

A: Given that Population mean=100  Standard deviation =5  We have to find 21.. probability of selecting…

Q: Assume that adults have IQ scores that are normally distributed with a mean of 98.7 and a standard…

A: Given data, μ=98.7σ=16.2P(X<x)=25%x=?

Q: he average amount of time in individual stopped by the police officers by the time they are 30 years…

A: The summary of the statistics is, x¯=6σ=1.2μ=5n=25 Assume the level of significance is, α=0.05

Q: . There is some reason to believe that the mean normal adult body temperature is not 98.6 degrees…

A: We want to test whether the mean normal adult body temperature is 98.6 F or not. Let μ denotes the…

Q: Assume that adults have IQ scores that are normally distributed with a mean of 100.5 and a standard…

A: Solution: Let X be the adults IQ score has normally distributed with mean μ=100.5 and standard…

Q: A normal population has mean u=56 and Standard deviation o=8. What is the 85th the population?…

A: We have given that  Mean, μ = 56 Standard deviation, σ = 8

Q: A set of data is normally distributed with a mean of 3.5 and a standard deviation of 0.6.  State…

A: Consider mean, μ=3.5               standard deviation, σ=0.6 Let the variable, X= area under a…

Q: Question 3 "An electrical firm produces light bulbs that have a length life that is approximately…

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Q: Which if the following statistics is an unbiased estimator of its population parameter?  Variance…

A: We know that ,the unbiased estimator is those value ,which are sample statistics of the population…

Q: What is the standard deviation in respiration rate for the three fish?

A: From given data we have N=3 Water temperature (degrees C) Fish respiration rate (bpm) 14 76…

Q: Assume that females have pulse rates that are normally distributed with a mean of p=75.0 beats per…

A: 1) c) Since the original population has a normal distribution, the distribution of a sample means…

Q: arger or smaller P-value? Juan and Mary want to test the null hypothesis that the mean length of…

A: Answer : The p-value is the probability of obtaining results at least as extreme as the observed…

Q: Claim: The standard deviation of pulse rates of adult males is less than   10   bpm. For a random…

A:

Q: A random variable is not normally distributed, but it is mound shaped. It has a mean of 18 and a…

A: GivenMean(μ)=18standard deviation(σ)=2sample size(n)=40

Q: Suppose that you have a box containing 1000 marbles and that your father wants to know if the mean…

A: # Given sample mean=3.85  Sample size n=100  Standard deviations=0.2  Testing of hypothesis  H0:…

Q: The scores on an IQ test are normally distributed with a standard deviation of 14 and a mean of 100.…

A: Let X be the IQ score from normal distribution with mean (μ) = 100 and standard deviation (σ) = 14…

Q: A survey found that women's heights are normally distributed with mean 62.1  inches  and standard…

A: Let "X" be the men who meet the height requiremnet. Refer Standard normal table/Z-table OR use…

Q: Claim: The standard deviation of pulse rates of adult males is less than 10 bpm. For a random…

A: Given, n=152 and σ=9.7 The claim is – "The standard deviation of pulse rates of adult males is less…

Q: Consider the test           ?0:????−????=3H0:μnew−μold=3   vs.  ?0:????−????<3H0:μnew−μold<3  What…

A: Given Data  : Sample from new material: Mean  is  106.122   ,  SD  is   4.7  and sample size is 14…

Q: We want to compare cholesterol levels between men and women, so we collect a sample of 20 women and…

A:

Q: The standard error of an estimator is the standard deviation of the estimator. True False

A: The Standard Error of the estimator is the Standard deviation of the estimator.

Q: The grade point average collected from a random sample of 150 students. Assume that the population…

A:

Q: A population has a mean of 250 and a standard deviation of 24. What value from the population has a…

A: Solution

Q: The scores on a test are normally distributed with a mean of 100 and a standard deviation of 20.…

A:

Q: A random variable is not normally distributed, but it is mound shaped. It has a mean of 18 and a…

A: given data population mean ( μ ) = 18population sd ( σ ) = 2sample size (n) = 13find mean of the…

Q: What is the test statistic for this procedure?

A: Assume that all conditions are met. The mean of the differences was 1.33 and the standard deviation…

Q: Assume that a sample is used to test a normal population mean u. A sample is of size 32 with a mean…

A:

Q: Animals of a given weight are operated on in a veterinary hospital. The dose of anesthetic A (in mg)…

A: a. The dose “D” that the vet should administer, in order that 99.9% of animals will be suitably…

Q: Test scores for a Statistics class have a mean of 81 with a standard deviation of 4. Test scores…

A: The provided information is, For statistics class:μ=81,σ=4For Calculus class:μ=75,σ=3.5   The…