A tire manufacturer would like to estimate the average tire life of its new all-season light truck tire in terms of how many miles it lasts. Determine the sample size needed to construct a 97% confidence interval with a margin of error equal to 2.300 milles. Assume the standard deviation for the tire life of this particular brand is 9,000 miles. The sample size needed is

Q: How large a sample should be selected to provide a 90% confidence interval with a margin of error of…

A:

Q: Based on previous school records, the standard deviation of the height of Grade 10 students in a…

A: Confidence interval is an interval such that the probability of the unknown parameter to be included…

Q: You measure 41 watermelons' weights, and find they have a mean weight of 47 ounces. Assume the…

A: Given that: n= 41.0 , x̄= 47.0 s= 2.5 At 90.0 % confidence level , z score= 1.645 So, 90.0 %…

Q: Denise is a professional swimmer who trains, in part, by running. She would like to estimate the…

A: Given,sample size(n)=20sample mean(x¯)=17.5  milesstandard deviation(s)=3.8  milesdegrees of…

Q: A professor is trying to find the average exam grade in his class. The sample mean should be within…

A: It is given that confidence level is 0.90, standard deviation is 12 and margin of error E is 5.

Q: An Army official wants to estimate the mean weight of a particular type of weapon.  He takes a…

A: Given that, Mean = 48.1 Standard deviation = 0.12 Sample size = 100 98% confidence level

Q: A researcher would like to estimate the mean weight of all adult male American alligators in the…

A: Sample size (n) = 105Sample mean (x̅) = 502Standard deviations (σ) = 29Significance level (α) = 1 -…

Q: The heights of pine trees at a local tree farm are known to follow a normal distribution with a…

A: Given: Sample Sizen=99Sample MeanX=121Standard Deviationσ=7 The z value corresponding to the area…

Q: the standard deviation of the 16 observations was 0.95 inches (again, the sample mean was 17.2).…

A: Given :  Standard deviation of the 16 observations was 0.95 inches & the sample mean was 17.2.…

Q: The average height of students at UT from an SRS of 11 students gave a standard deviation of 3.0…

A: Givensample size(n)=11standard deviation(s)=3.0confidence level=95%

Q: The quality-control manager of a chemical company randomly sampled twenty 100-pound bags of…

A: It is given that the sample variance is 6.62 and the sample size is 20.

Q: In a random sample of twelve ​people, the mean driving distance to work was 21.5 miles and the…

A: Solution

Q: In a random sample of nine people, the mean driving distance to work was 25 miles the sample…

A:

Q: A professor wants to estimate how many hours per week her students study. A simple random sample of…

A: Sample size Sample mean Confidence level is 99% i.e., 0.99.Population standard deviation

Q: In a random sample of 15 ​people, the mean driving distance to work was 18.5 miles and the standard…

A:

Q: A professor wants to estimate how many hours per week her students study. A simple random sample of…

A:

Q: In a random sample of five ​people, the mean driving distance to work was 19.9 miles and the…

A: Given Sample size, n = 5 Degree of freedom, n-1 = 4 Sample mean, x = 19.9 miles Sample standard…

Q: he average weight of 20 randomly selected cars was 3500 pounds. The sample standard deviation was…

A: given data, n=20df=n-1=20-1=19x¯=3500 pounds s=315 pounds CI=0.90α=1-0.90=0.10

Q: How much do wild mountain lions weigh? Six adult wild mountain lions are captured and released.…

A: Given data , 68, 104, 128, 122, 60, and 64.

Q: Find Ta/2 for a 90% confidence interval and a sample size of 30.

A: 90% confidencve inetrval for Sample size : n = 30Critical value of T = ?

Q: The mean length of all the telephone calls would have to be estimated. In sample of 14 calls, the…

A: Given:

Q: The total of individual weights of garbage discarded by 17 households in one week is normally…

A:

Q: You know that the average amount of protein consumed by 254 men in a study is 75 grams a day, when…

A:

Q: A food snack manufacturer samples 9 bags of pretzels off the assembly line and weighs their…

A: Given information Sample size (n) = 9 Sample mean x̅ = 15.2 oz Standard deviation (s) = 0.50 oz…

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

A:

Q: A runner wants to know her average mile running time. She records a sample of 25 running times. The…

A: Solution: Let X be the mile running time. From the given information, x-bar=6.5 minutes, s=0.7…

Q: A recent study of 28 city residents showed that the mean of the number of years they lived at their…

A: The formula of confidence interval for the population mean is given by                  confidence…

Q: SAT scores are normally distributed with a mean of 1,500 and a standard deviation of 300. An…

A: Given,standard deviation(σ)=300margin of error(E)=15α=1-0.95=0.05α2=0.025Z0.025=1.96

Q: You measure 29 backpacks' weights, and find they have a mean weight of 46 ounces. Assume the…

A:

Q: You measure 41 watermelons' weights, and find they have a mean weight of 79 ounces. Assume the…

A: Mean = 79Standard deviation = 2.4Sample size = 41

Q: The total of individual weights of garbage discarded by 15 households in one week is normally…

A: The total of individual weights discarded by 15 households is normally distributed with mean 29.7…

Q: Gary observed the fuel efficiency of his SUV. After the first 100 times he filled up the tank, he…

A:

Q: The mean score of a random sample of 22 students’ applicants who took the college entrance…

A: Given :    Sample size (n) =22

Q: market research company wants to estimate the average age of car owners in a city. A random sample…

A: The formula for the confidence interval for the mean is (sample mean - E, sample mean + E), where E…

Q: A food snack manufacturer samples 11 bags of pretzels off the assembly line and weighs their…

A:

Q: A popular weight loss program claims users will lose weight each month. Linda samples 25 dieters and…

A: We have given that,  Sample mean (x̄) = 10 pounds, standard deviation (s) = 2 pounds and sample size…