The heights of 9 men were taken with sample mean of 165 cm and standard deviation 5 cm. The heights of 7 Japanese women were taken with sample mean of 150 cm and standard deviation 3 cm. Assuming that the population standard deviations for heights of men and women are both the same, construct the 95% confidence interval for the difference in mean heights between men and women.

Q: Wheel thickness on a train is random because wear and tear causes the wheel to wear down. The…

A: We have given that,  Sample mean or average (x̄) = 8.29, standard deviation (σ) = 0.52 and sample…

Q: Researchers found that in certain counties in the country, females spend an average of 65 days in…

A: standard deviationσ=4n=36x¯=65

Q: standardized placement test was given to 10 boys and 11 girls who applied for a certain job. The…

A:

Q: calculating the mean weight of a packet of Nachos?

A:

Q: he number of square feet per house are normally distributed with an unknown population mean and…

A: Given information- Sample size, n = 33 Confidence level, C = 90% Significance level, α = 0.1 So,…

Q: Among 157 Hispanic American men ,the mean systolic blood pressure was 146 mm Hg with a standard…

A: Hypotheses: Null hypothesis: H0: µ = 140. Alternative hypothesis: H1: µ >140. Here, the…

Q: A bakery owner is trying out new donut recipes that have less fat. The current recipe have an…

A: Given: Mean of current recipe is μ=175 grams. Sample size of donut baked is n = 12. Mean of new…

Q: An agronomist would like to estimate the average weight of all Indian River County grapefruits. The…

A:

Q: he effects of mentoring on intelligence scores. He wanted to know as a baseline what the averag

A: mean(μ)=100standard deviation(σ)=16  n=50    let X~N(100,16)

Q: The National Health Statistics Reports published in 2018 reported that a sample of 360 ten-year- old…

A: Null and alternate hypotheses: The investigator is specifically interested to test whether the mean…

Q: The mean hours of worked for United Airlines pilots is 46 hours/month based upon a sample of 25…

A: Given: Sample size, n=25 Sample mean, X=46 hours Sample standard deviation, s=3 hours The level of…

Q: The mean IQ for the entire population in any age group is known to be 100 with a standard deviation…

A: Given: μ0=100n=72x¯ = 103.4s=20.2α = 0.05 Part 1: The null and alternate hypothesis are, H0: μ0 =…

Q: Sketch a picture of this situation. Label and scale the horizontal axis and shade the region(s)…

A: n1 = 29n2 = 16 x1 = 4x2 =5 s1 = 0.7s2 = 1.1

Q: The average weight of 36 randomly selected school buses was 4150 pounds with a standard deviation of…

A: Given data,x=4150σ=480n=36z-value at 99% confidence is Zc=2.576

Q: A marketing firm wants to estimate the difference in the mean amount of caffeine in two brands of…

A:

Q: The mean number of English courses taken in a two-year time period by male and female college…

A: Given, Male: x1 = 4, s1 = 0.9, n1 = 29 Female: x2 = 5, s2 = 1.1, n2 = 16 α = 0.05

Q: Researchers conducted a study to investigate whether there is a difference in mean PEF in children…

A: Given, n1 = 100, n2 = 100 -x1 = 20, -x2 = 308 s1 = 64, s2 = 77

Q: what would the 95% confidence limits for a sample of 120 with a mean of 51 and a standard deviation…

A: It is given that mean and standard deviation are 51 and 12, respectively.

Q: A sample of 13 concerts showed their average noise levels were 82 decibels and their standard…

A: Solution: Let X be the noise level From the given information, x-bar=82 decibels, s=7 decibels and…

Q: Two machines used to fill soft drink containers are being compared. The number of containers filled…

A: Given Information: For machine 1:    x¯1=69.2, s¯1=2.1 , n1=26 For machine 2:   x¯2=68.5, s¯2=3.1 ,…

Q: researcher was interested in the mean corn yeild for farmers in Illinois. She took an SRS of 28…

A: Given that  Margin of error =E =3.5 Population standard deviation =13.25 95% confidence level.

Q: To determine whether a new drug designed to lower a person’s heart rate is effective or not, Dr.…

A: Since sample size is large and population standard deviation is known, z-test is appropriate in this…

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: Assume that adults have IQ scores that are normally distributed with a mean of 101.7 and a standard…

A: GivenMean(μ)=101.7standard deviation(σ)=16.8

Q: The average measured verbal IQ (IQV) scores of children is 100.  In a sample of 20 children, the…

A: Population mean (µ) = 100Standard deviations (σ) = 18.5Sample size (n) = 20Sample mean (x̅) =…

Q: x¯ = Margin of error at 90% confidence level = 90% confidence interval =

A: Given: n=8 Confidence level=90% Height, X 67 66 64 75 63 67 72 71

Q: A laboratory tested 78 chicken eggs and found that the mean amount of cholesterol was 224 milligrams…

A:

Q: An old medical textbook states that the mean sodium level for healthy adults is 142 mEq per liter of…

A: GivenMean(x)=136standard deviation(σ)=14sample size(n)=13significance level(α)=0.05

Q: Grace is planning to transfer in Alabang to save on gas consumption. The monthly gas consumption of…

A:

Q: student a received a score of 91 on a test whose scores had a mean of 82 and a standard deviation of…

A: Given data,For Student AMean μ=82sd      σ=6Score is x=91For Student BMean μ=80sd      σ=4Score is…

Q: The distribution of study times for first-year students follows a normal distribution with a…

A:

Q: Dr. Moore wanted to estimate the mean cholesterol level for all adult men living in Hartford... He…

A:

Q: A random sample of 84 products is selected and sample mean and standart deviation are found to be…

A: We have to find level of confidence.

Q: An old medical textbook states that the mean sodium level for healthy adults is 138 mEq per liter of…

A:

Q: The age when smokers first start from previous studies is normally distributed with a mean of 13…

A: Given,sample size(n)=22sample mean(x¯)=13.8standard deviation(σ)=2.1α=1-0.90=0.1α2=0.05Z0.05=1.645…

Q: Suppose the mean pulse rate of college students is 68 beats per minute with a standard deviation of…

A:

Q: The age of managers in particular industry is normally distributed with mean μ=35. A group of 30…

A:

Q: The length of the western rattlesnake is normally distributed with a mean of 42 inches and a…

A: Determine the length of the snakes that the 95% of western rattlesnakes that are longer than. The…

Q: An old medical textbook states that the mean sodium level for healthy adults is 139 mEq per liter of…

A: From the provided information,

Q: The average height of the students in a famous college in the city is unknown but the standard…

A: Given, X=7.1n = 55σ=0.10

Q: The General Social Survey polled a sample of 1056 adults in the year 2015, asking them how many…

A: From the provided information,

Q: 95% confidence interval of the population mean

A: Given : Sample Size, n = 40 Sample Mean, x̄ = 500 sample standard…

Q: The population standard deviation is 5 inches. The heights of 7 randomly selected students are 73,…

A: Given that  Population standard deviation (σ) = 5 inches  heights of 7 randomly selected students…

Q: sample of 37 inchworms in Cititon Park was collected and measured. Their lengths had a mean of 2.56…

A: Given:  Sample size n=37  Sample mean(xbar) x¯ =2.56  Standard deviation( ?)=0.09  To find 95%…

Q: The distribution of scores has a mean of 92 and standard deviation of 6. Explain why these scores…

A: A normal distribution has 15.86 percentage values more than one standard deviation units above the…

Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.