A medical researcher wants to investigate the amount of time it takes for patients' headache pain to be relieved after taking a new prescription painkiller. She plans to use statistical methods to estimate the mean of the population of relief times. She believes that the population is normally distributed with a standard deviation of 17 minutes. How large a sample should she take to estimate the mean time to within 3 minutes with 98% confidence? Sample Size =

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

A: Solution-: Let, X= The college students have loneliness scores  Given: We find,

Q: A group of data has a mean of 69 with a standard deviation of 5. What is the probability of finding…

A: Given the mean= 69 and standard deviation = 5 So, z score of 61 is:

Q: Pandora, the owner of a food delivery app, knows from experience that the time needed to assemble a…

A:

Q: In a college entrance exam, the average score of 1,000 test takers is 150 with a standard deviation…

A:

Q: A medical researcher wants to investigate the amount of time it takes for patients' headache pain to…

A: Given information Standard deviation (σ) = 23 Confidence level = 0.91

Q: A distribution has a mean of 16 and a standard deviation of 6. What is the Z score that corresponds…

A: A value from any normal distribution can be transformed into its corresponding value on a standard…

Q: A normal distribution has a mean of 100 and a standard deviation of 15. What is the median for this…

A: Given Mean μ=100, standard deviations σ=15

Q: A company that manufacturers batteries for cell phones wants to estimate the mean number of hours…

A: Given: Standard deviation (σ) = 3.85 Margin of error (E) = 1.5 Confidence level = 95%

Q: A large group of students took a test in Statistics and Probability and the final grades have a mean…

A: Given: μ=70 and σ=10. The z-score is calculated as-z=x-μσ

Q: In the past, a chemical company produced 880 pounds of a certain type of plastic per day.  Now,…

A: From the provided information, Sample size (n) = 50 Sample mean (x̅) = 871 Sample standard deviation…

Q: A normally distributed variable has a mean of 75 and a standard deviation of 2. What is the z-score…

A: The z-score for 69 is obtained below: From the given information, the value of mean is 75 and…

Q: Do the data support your claim at the 1% level?

A: The summary of the statistics is, The type of test is right tailed test

Q: The lifetime of light produced by a company is normally distributed with standard deviation of 80…

A: Let X : Lifetime of light produced by a company is normally distributed with  Standard deviation (σ)…

Q: A group of data has a mean of 65 with a standard deviation of 5. What z-score is possible if the…

A: According to the provided information,

Q: A set of exam scores is normally distributed and has a mean of 78.1 and a standard deviation of 8.1.…

A: We have given that , Mean = 78.1 , Standard deviation = 8.1 , X = 60

Q: The weight of potato chips in a small​-size bag is stated to be 6 ounces. The amount that the…

A: It is given that the mean and standard deviation are 6.1 ounces and 0.08 ounces, respectively.By…

Q: In a study of 90 grade nine students, the mean number of hours per day they are online for  their…

A: We have given that Mean(µ) = 4.8 Standard deviation of the population (σ) = 0.4  n = 9

Q: The dean of a college wants to use the mean of a random sample to estimate the average time students…

A: The sample size is obtained below: From the given information, the margin of error (ME) is 5…

Q: A marketing specialist wants to estimate the average amount spent by visitors to an online…

A:

Q: An advertising executive wants to estimate the mean amount of time that consumers spend with digital…

A: a) The sample size is 117 and it is obtained below: From the given information, the population…

Q: How many commuters must be randomly selected to estimate the mean driving time of Chicago commuters?…

A: Solution: It is given here that the confidence level is 95% The margin of error, E = 3 The…

Q: A university dean of students wishes to estimate the average number of hours students wish to spend…

A: The formula for the sample size is as follows:

Q: A psychologist has developed a new test of spatial perception and she wants to estimate the mean…

A:

Q: An electrical firm manufactures light bulbs that have a length of life that is approximately…

A: From the given information,   Margin error = 13 Standard deviation = 35   The objective is to find…

Q: The owner of a shopping mall wants to estimate the mean length of time shoppers spend in the mall.…

A:

Q: In a Scrabble tournament, the scores were normally distributed and the mean score was 420.2 points…

A:

Q: The quality grade-point averages of 300 college freshmen follow approximately a normal distribution…

A:

Q: A medical statistician wants to estimate the average weight loss of people who are on a new diet…

A: Given,standard deviation(σ)=8margin of error(E)=2α=1-0.94=0.06α2=0.03Z0.03=1.8808       (from…

Q: In a Scrabble tournament, the scores were normally distributed and the mean score was 420.2 points…

A:

Q: How large of a sample is required if we want to estimate the mean price of a five year old Corvette…

A: Obtain the critical value at 90% confidence level:It is given that the standard deviation value is…

Q: A football coach claims that the average weight of all the opposing teams’ members is 225 pounds.…

A: Given: n= 50.0 ,x̄= 230.0 ,σ= 15.0 µ= 225.0

Q: The dean of a college wants to use the mean of a random sample to estimate the average time students…

A:

Q: Companies who design furniture for elementary school classrooms produce a variety of sizes for…

A:

Q: Brenda has collected data to find that the finishing times for cyclists in a race has a normal…

A: Given the finishing time for cyclists in a race has normal distribution with mean 143 minutes and…

Q: The quantitative data set under consideration has roughly a bell-shaped distribution. Apply the…

A: The size of the data set is 80.

Q: The time it needs a communications worker to arrange a domestic phone call is normally distributed…

A: It is given that the mean is 50 seconds and standard deviation is 8 seconds.

Q: A university dean wishes to estimate the average number of hours that freshmen study each week. The…

A:

Q: The weight of potato chips in a large-size bag is stated to be 24 ounces. The amount that the…

A:

Q: In a standardized exam the mean score is 400 with a standard deviation of 50. If a random sample of…

A: Given that  μ= 400 , σ= 50 , n = 25

Q: A medical statistician wants to estimate the average weight loss of people who are on a new diet…

A:

Q: Professor Brown administered an achievement test, which as he remembers from years of experience,…

A: Given: Population mean score(μ)=85 Sample mean(X¯)=89 Sample standard deviation(s)=14 n: no of…

Q: A quantitative data set has a size 50. At least how many observations lie within 3 standard…

A: Suppose X is a random variable with expectation, μ and standard deviation, σ. Then, for any positive…

Q: A computer scientist estimates that the proportion of users that properly back up their data is p =…

A: Given data,n=380 usersp=0.304Find the mean and standard deviation of sample proportion?

Q: A medical statistician wants to estimate the average weight loss of people who are on a new diet…

A: Given Data: ME=4/2=2 σ=8   z-value corresponding to 97% of CI=2.17

Q: A medical statistician wants to estimate the average weight loss of people who are on a new diet…

A:

Q: A vending machine automatically pours soft drinks into cups. The amount of soft drink dispensed into…

A: Let X be the amount of soft drink dispensed in to a cup. Given that X follows normal distribution…

Q: a medical researcher wants to investigate the amount of time it takes for patients' headache pain to…

A: Since we know population standard deviation, use z-distribution to find z-critical value. Find…

Q: A sociologist found that in a sample of 45 retired men, the average number of jobs they had during…

A: Given : population mean ,u = 7.2  population standard deviation,σ = 2.3

Q: college dean  wants to use the mean of a random sample to estimate the average time students take to…

A:

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

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.