A study is going to be conducted in which a mean of a lifetime of batteries produced by a certain method will be estimated using a 90% confidence interval. The estimate needs to be within +/- 2 hours of the actual population mean. The population standard deviation σ is estimated to be around 25 hours. The necessary sample size should be at least _______. 21 923 100 35 423

Q: If a population has a mean of 228.8 and a standard deviation of 35.5 then a sampling distribution…

A: Given that, mean is 228.8 and standard deviation is 35.5. We will use z-standard normal…

Q: How many light bulbs must a company test to determine the mean number of hours that they will last?…

A: Given that, The company wants to be 90% confident that their mean is within 40 hours of the…

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 20 for the population…

A: GIVEN DATA,an IQ test mean is 100 and standard deviationis 20 for the population of normal adults…

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 22 for the population…

A: Given information- Population standard deviation, σ = 22 Confidence interval = 0.90 Significance…

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 12 for the population…

A: Givenstandard deviation(σ)=12Marign of error(E)=7c=99%α=1-0.99=0.01α2=0.005zα2=z0.005=2.5758   (from…

Q: An 10 test is designed so that the mean is 100 and the standard deviation is 13 for the population…

A: It is given that confidence level is 0.90, standard deviation is 13 and margin of error E is 5.

Q: The brain volumes ​(cm3​) of 20 brains have a mean of 1197.8cm3 and a standard deviation of…

A: Given information- Sample mean x=1197.8 cm3Sample standard deviation s=124.5 cm3Sample size, n=20 We…

Q: If the sample has standard deviation 2.1, what is a reasonable approximation to the range of this…

A: It is given that the standard deviation of the data is 2.1.

Q: The required sample size is (Round up to the nearest integer.) Would it be reasonable to sample this…

A:

Q: The population distribution is normally distributed and has a mean of 13.6 and a standard deviation…

A: Normal distribution is a continuous distribution which has many real life applications. Normal curve…

Q: A population has a mean μ=147 and a standard deviation σ=30. Find the mean and standard deviation of…

A: The mean of the sampling distribution of sample means: Plug in all the values in the formula, we…

Q: A population has a mean μ=83 and a standard deviation σ=2424. Find the mean and standard deviation…

A: Given dataMean μ=83Standard Deviation σ=24Points on sampling distribution of the sample mean:If the…

Q: How many retired people should be sampled if we want to calculate with 92% confidence the true mean…

A: The provided information are: Confidence level = 92% Margin of error (E) = 0.8 Population standard…

Q: A sample of size 60 will be drawn from a population with mean 31 and standard deviation 6 .Find…

A: Given that.   X~N( μ , ?)   μ=31     , ?=6   Z-score =( x - μ )/?

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 17 for the population…

A: Givenstandard deviaion(σ)=17Margin of error(E)=4confidence level =…

Q: A population has a mean μ=169 and a standard deviation σ=21. Find the mean and standard deviation…

A: Mean()=169standard deviation()=21sample size(n)=46

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 12 for the population…

A: We want to find the sample size (n)

Q: A particular brand of coffee contains the average of 110mg of caffeine per cup with a standard…

A:

Q: Given that the population standard deviation equals 273 and the sample size consists of 741…

A: Given information- Population standard deviation, σ = 273 Sample size, n = 741 We have to find the…

Q: For men heights are normally distributed with a mean of 69 inches and a standard deviation of 2.8…

A: The random variable X is heights of the men. It is normally distributed. X~N(μ=69,σ=2.8) The sample…

Q: A population has a mean μ=85 and a standard deviation σ=28. Find the mean and standard deviation…

A:

Q: A population has a mean μ=79 and a standard deviation σ=21. Find the mean and standard deviation…

A:

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 10 for the population…

A: Given Standard deviation=10 Margin of error=3 95% confidence level

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 16 for the population…

A:

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.