A traffic officer suspects that the mean number of car accidents every week is 4. A sample of 16 weeks showed a mean of 7. If the variance of car accidents in the population is 4,

Q: Suppose a population has three values 13, 17 and 24. What is its variance?

A: Given: n=3 The mean of the data is obtained as below: Mean=∑xn=13+17+243=543=18 The mean is 18.

Q: A population with a mean of µ = 15 has 40 scores. What is X?

A:

Q: A population of marine gastropods has shell lengths that are normally distributed with a mean of 7…

A: We have to find given probability.

Q: To obtain a maximum amount of variance, an item ought to have a degree of difficulty of what?

A: To obtain a maximum amount of variance an item ought to have a degree of difficulty is the number of…

Q: The researchers hypothesized that there would be a correlation between how much people studied and…

A: Solution: From the given information, the researchers hypothesized that there would be a correlation…

Q: What is the variance of number of Sundays on a nonleap year?

A:

Q: The mean and standard deviation of a set of 100 observations were Worked out as 40 and 5…

A: We have given that Number of observations(n)=100  Corrected mean=40 Standard deviation=5  Mistaken…

Q: how to find the variance?

A: Variance is a measure of variability. It is computed by the average of squared deviations from the…

Q: the variance of a data set is 144 and mean is 72 then coefficient of variance is

A: Given,variance(σ2)=144mean(x¯)=72

Q: If the variance of a national accounting examination is 828, how large a sample is needed to…

A: Given data: Variance  = 828 Margin of error = 4 points Confidence level = 99 % To calculate the…

Q: A researcher calculates the variance of her sample to be s = -6. , what would you tell the…

A: Here's the explanation for this as follows; The sample variance, s², is used to calculate how varied…

Q: A professor has a sample of 30 student scores with a mean of 10, a variance of 9, and a standard…

A: Given, A professor has a sample of 30 student scores with a mean of 10, a variance of 9, and a…

Q: In a herd of cattle, the mean milk production is 160 lbs per day with a variance of 400 Ibs per day.…

A: Given that the mean milk production in the cattle is,  μ=160 lbs per day & with a variance,…

Q: For any quantitative population with a finite variance, the proportion of data points less than 2…

A: Given :- For any quantitative population with a finite variance, the proportion of data points less…

Q: a sample of 60 grade 9 student age was obtained to estimate the mean age of all grade 9 students. x…

A: A sample of 60 Grade 9 students' ages was obtained to estimate the mean age of all Grade 9 students.…

Q: A population has a mean of μ = 50, a variance of σ2 = 9, and a standard deviation of σ = 3.  The…

A:

Q: A population of marine gastropods has shell lengths that are normally distributed with mean μ=7mm…

A: For large sample size (n>30), let X be a random variable following normal distribution with mean…

Q: The accounting department analyzes the variance of the weekly unit costs reported by two production…

A: See the handwritten solution

Q: what happens to the F-statistic if two variances are different?

A: The two variances are different hence the F-statistic are as follows,

Q: A researcher measures the amount of food consumed by each dog in her lab. She finds that the mean…

A: In statistics, variance is the average squared distance of each data points from the population…

Q: A distribution has a mean of 75 and a median of 70. This distribution is probably positively skewed

A:

Q: If you have a Pearson correlation coefficient of .30, what is the proportion of variance accounted…

A:

Q: A sample of 30 distance scores measured in yards has a mean of 7, a variance of 16, and a standard…

A: Given statistics:Consider the variable x represents the distance scores in yards.The given…

Q: The accounting department analyzes the variance of the weekly unit costs reported by two production…

A:

Q: The foreman at a large plant estimates that there are defective parts about 1% of the time.  If the…

A: It is given that n =20,000 and p = 0.01.

Q: What is the value of the variance if the mean of a frequency distribution is 100 and the coefficient…

A:

Q: A population has a mean of μ = 100, a variance of σ2 = 9, and a standard deviation of σ = 3.  The…

A:

Q: A SAMPLE SIZE OF 36 WAS DRAWN AND ITS MEAN WAS FOUND TO BE 80. TEST WHETHER THIS SAMPLE COULD HAVE…

A:

Q: If the probability that an object dropped from a certain height will strike the ground is 80 percent…

A: Solution- Given that , let p denote the probability that an object dropped from a certain height…

Q: (a) Among the next 210 customers, what are the mean and variance of the number who pay with a debit…

A: Consider the events A, B and C that represents the customers who pay with a credit card, debit card,…

Q: A correlation of +.20 means that [blank] of the variance in the outcome variable is accounted for by…

A: Solution: From the given information, r=0.20.

Q: If the correlation is .8, then 40% of the variance is explained?

A: The given statement is incorrect.

Q: is 32, the estimate of the variance of the model errors is

A: Given: multiple regression model with no of regressors k=3 and sample size n=20  also error sum of…

Q: Determine the mean and the variance of X.

A: Given that  f(x) = 0.125 x    for 0<x<4   We know that  Mean = E(x) = ∫x.f(x) dx variance V(x)…

Q: What is the variance of a data set with mean score of 87.5 and a standard deviation of 2?

A:

Q: A consultant for a large university studied the number of hours per week freshmen watch TV versus…

A: Let μ1 denotes the mean number of hours per week freshmen wash TV, and μ2 denotes the mean number of…

Q: Mr Chimbukutu, owner of a bakery said that the average weekly production level  of his company was…

A: We have given that  Mean(µ) = 11398 Standard deviations (σ) = √ 49729 = 223

Q: A researcher says that 50% of the variance in blood pressure can be predicted from HR and that blood…

A: In this question we have the value of coefficient of determination which is equal to 0.50 and we…

Q: Describe a scenario where a researcher could use an F-test for the equality of two variances to…

A: F-test can be used when we are given two groups and we want to compare the differences in the…

Q: Explain whether homogeneity of variance is satisfied for this analysis, and be clear on how you…

A: Homogeneity of Variance: Homogeneity of variance (homoscedasticity) is a crucial assumption shared…

Q: If the mean of grades in statistics = 65 and the variance : 400 , then the Z score of grade 50 =

A:

Q: a population with a known mean but an unknown variance.

A: We have to study a single sample's mean is being compared to the population with a known mean but…

Q: In analysis of variance, the F-ratio is a ratio of

A: F ratio is a ratio of 2 variances or two mean squares. Mean squares are simple variances that…

Q: If the variance of a national accounting examination is 900, how large a sample is needed to…

A:

Q: Once the correlation coefficient is known, how can we find the amount of the shared variance?

A: Concept:  correlation coefficient measures the degree of linear relationship between two variables.

Q: If the probability of hitting an object is 0.8, what would the variance be?

A: Given problem Given that   If the probability of hitting an object is 0.8, what would the variance…

Q: Suppose a researcher pbserves a population of 12 people and computes SS=204. What is the variance?…

A: The population size is N=12. The sum of squares is SS=204. Need to obtain: the variance and the…