A recent survey of 200 people revealed that the mean time spent in watching television of teenagers is 4.2 hours. Previous national records say that the mean time was 3.8 hours with standard deviation of 0.3 hours. Do the survey results significantly differ from previous records at 0.05 level of significance?

Q: Suppose the exam average in a class is 82% with a standard deviation of 6. What proportion of…

A:

Q: Construct a 95%95% confidence interval for the true difference in mean battery life between Steve’s…

A: The pooled variance is, sp2=n1-1s12+n2-1s22n1+n2-2=12-14.33+7-16.8212+7-2=28.2841 The pooled…

Q: A recent survey was conducted to compare the cost of solar energy to the cost of gas or electric…

A:

Q: A boxer would like to know the mean diameter of a navel orange. If the standard deviation is 0.3…

A: Given Standard deviations=0.3 Margin of error=0.1 At 95% confidence z=1.96

Q: According to a recent survey, the population distribution of number of years of  education for…

A: What is the standard error of mean?

Q: if an approxemitly  bell shaped distribution has a mean of 30 and standard deviation of 5, what…

A: Given that  X~N( μ = 30 , ? = 5 ) μ = 30 , ? = 5 Formula for Z-score Z-score =( x - μ )/?

Q: Suppose you found that the average sea- faring bird can fly 8,000 km without stopping. The wandering…

A:

Q: Does a small standard deviation signify more or less uncertainty in the data ? Explain.

A:

Q: Scores on a recent national statistics exam were normally distributed with a mean of 80 and standard…

A: Obtain the standard z-score for X equals 89 The standard z-score for X equals 89 is obtained below:…

Q: What value lies under a standard score of 1.5 in a distribution having a mean of 55 and standard…

A:

Q: The gestation period for human births can be taken as normally distributed with a mean of 256 days…

A: From the given information, the gestation period for human births can be taken as normally…

Q: A quality control company was hired to study the length of meter sticks produced by a certain…

A: The mean length would be at the 92nd percentile is obtained below: here, P (Z < z) = 92% P (Z…

Q: In 2019, the amount of money that motorists spent on gas had a normal distribution with a mean of…

A: Given Information Number of persons sampled (n) = 2400 Mean (µ) = 900 Standard deviation(σ) = 100…

Q: At the 0.05 level of significance, is there evidence that the mean life is different from 375hours?

A: Here sample size n =64 Population standard deviation = 100 hours Sample mean = 350 hours Here claim…

Q: The gestation period for human births can be taken as normally distributed with a mean of 266 days…

A: Given:

Q: A particular leg bone for dinosaur fossils has a mean length of 5 feet with a standard deviation of…

A: Given, A particular leg bone for dinosaur fossils has a mean length of 5 feet with a standard…

Q: A study of the Physics and Astronomy department has found that 95% of the graduate students drink…

A: Explanation:Here given the two means and find out the standard deviation of the sample follows the…

Q: Suppose the scores of students on an exam are normally distributed with a mean of 454 and a standard…

A:

Q: The credit card balances on 1,000 accounts at the Jefferson Valley Bank have a mean of $760 and a…

A: mean = 760 s = 120 n = 1000

Q: According to a recent study, if a person smoked, the average number of cigarettes smoked per day was…

A:

Q: Suppose that IQ scores have a bell-shaped distribution with a mean of 104 and a standard deviation…

A: Given, Mean, mu= 104 Standard deviation, sigma= 17 We know that,  Z score= (X-mu)/sigma

Q: A manufacturer claims that the mean lifetime of its lithium batteries is 1400 hours. A homeowner…

A: Given, Claim: A manufacturer claims that the mean lifetime pf its lithium batteries is 1400 hours.…

Q: An instructor in a large lecture class found, at the end of the semester, that the total point…

A: The provided information is:

Q: The test scores of students in a class test has a mean of 70 and with a standard deviation of 12.…

A: Given,mean(μ)=70standard deviation(σ)=12

Q: Nationally, the per capita monthly fuel oil bill is $110. A random sample of 36 cities in the…

A: Let μ denotes the population mean per capita monthly fuel oil bill. The national per capita monthly…

Q: The combined math and verbal scores for students taking a national standardized examination for…

A: μ = 800 σ = 190

Q: Suppose that that the average BMI of the patients at Beth Israel Deaconness Medical Center is 30…

A:

Q: The students of a large university in Luzon were studied regarding their hours of sleep at night.…

A: As the distribution of the hours of sleep can be modeled as normal distribution with mean μ of 6.9…

Q: Suppose that IQ scores have a bell-shaped distribution with a mean of 100 and a standard deviation…

A:

Q: A line for tickets to a broadway show had a mean waiting time of 20 minutes with a statistic…

A: Given, Mean = μ = 20Standard deviation = σ = 4       To find, P (X > 28) = ?

Q: Suppose the scores of students on an exam are normally distributed with a mean of 253 and a standard…

A: From the provided information, Mean (µ) = 253 Standard deviation (σ) = 80

Q: It has been found that with the standard dosage of a drug, the change in people’s uric acid levelis…

A: Given X is normal Distributed with mean µ = 240.0 and standard deviation σ = 60.0 now will using…

Q: The waiting time for patients at a local walk-in health clinic follows a normal distribution with a…

A: We have to find hypothesis..

Q: Suppose the average height of a two year old male is normally distributed with a mean of 34.2 inches…

A: Given, Mean = μ = 34.2standard deviation = σ = 2.9

Q: Assume the average amount of caffeine consumed daily by adults is normally distributed with a mean…

A: The detailed solution is as follows below:

Q: Suppose that the distance of fly balls hit to the outfield is normally distributed with a mean of…

A: Let X denote the distance of fly balls hit to the outfield is normally distributed with a mean of…

Q: The combined math and verbal scores for students taking a national standardized examination for…

A:

Q: The hotel room rate in Miami, Florida is normally distributed with a mean of $286 per night. Assume…

A:

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: Suppose that IQ scores have a bell-shaped distribution with a mean of 96 and a standard deviation of…

A: 17. Empirical rule (68 – 95 – 99.7 rule): For a bell shaped distribution (normal) the empirical rule…

Q: An analyst found that the average amount of money in bank accounts at his/her bank is $2,000 with a…

A:

Q: Suppose there is a city where the mean cost per month of a one-bedroor apartment is $1,500, with a…

A: The percentage of one bedroom apartments in the city cost between $750 and $1000 is,

Q: The average score on the verbal portion of the college entrance exam is 453, with a standard…

A: From the provided information, Sample size (n) = 137 Sample mean (x̅) = 502 Population standard…

Q: The combined math and verbal scores for students taking a national standardized examination for…

A: Given: Mean of combined scores of students = 880 Standard deviation of combined scores of students =…

Q: A recent newspaper article reported the results of a survey of well-educated suburban parents. The…

A: Given that 2-year-old children watching an average of 60 minutes of television each day watching an…

Q: The General Social Survey  asked a sample of 1298 people how much time they spent watching TV each…

A: From the given information,

Q: The national scores on an exam were normal distributed with a mean of 428 and a standard deviation…

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

Q: Cushman and Wakefield reported that the average annual rent for office space in Tampa was $17.63 per…

A: H0 : ? =17.63     H1 : ? ≠17.63     Population mean = ? = 17.63 Sample S.D = s =3.64…

Q: College students, in general, have a mean of 60 and a standard deviation of 8 on a measure of…

A: According to the provided information, Mean (μ) = 60 Standard Deviation (σ) = 8

Types of Bias

Statistics is the study of data collection, organization, analysis, interpretation, and presentation. Statistical bias is a characteristic of a statistical technique or its findings in which the expected value deviates from the actual root quantitative parameter being estimated. According to the actual definition of bias, it refers to the tendency of a statistic to overestimate or underestimate a parameter.