A manufacturer claims that the mean lifetime, μ , of its light bulbs is 50 months. The standard deviation of these lifetimes is 7 months. One hundred fifty bulbs are selected at random, and their mean lifetime is found to be 51 months. Can we conclude, at the 0.05 level of significance, that the mean lifetime of light bulbs made by this manufacturer differs from 50 months? Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places, and round your responses as specified below. (If necessary, consult a list of formulas.)

Q: The mean wingspan of a sample of 31 birds of a particular species is 30 inches.  The standard…

A: Sample size n =31 Sample mean=30 Population standard deviation =4

Q: The lengths of pregnancies in a small rural village are normally distributed with a mean of 268.5…

A: It is given that the length of pregnancies is normally distributed with mean 268.5 and standard…

Q: The lengths of pregnancies in a small rural village are normally distributed with a mean of 261.5…

A: Given data, Mean=261.5 sd=17.6 In what range would you expect to find the middle 68% of most…

Q: An important indicator of lung function is forced expiratory volume (FEV), which is the volume of…

A: Given that Population mean=3000 Standard deviation =400  We have to find the correct statement…

Q: Suppose the lifetimes of a certain lightbulb are normally distributed with a standard deviation of…

A: From the provided information, Standard deviation (σ) = 100 Let µ be the required mean. X~N (µ, 100)…

Q: researcher in a large university claimed that the mean health care expenses differ from the national…

A: From the given information, Consider,  μ=$1570n=50x=$1680s=$180α=0.05

Q: 21. What is the probability of selecting someone from the general population at random who would…

A: Given that Population mean=100  Standard deviation =5  We have to find 21.. probability of selecting…

Q: A researcher wishes to see if there is a difference in the manual dexterity of athletes and that of…

A: Sample mean for athletes x¯1=89 Sample mean for band members x¯2=95 Standard deviation σ=7.4 .…

Q: An experiment was conducted to estimate the effect of smoking on the blood pressure of a group of 31…

A: The sample size is 31, sample mean is 9.1 and sample standard deviation is 5.3.

Q: Suppose that the hemoglobin levels among healthy females are normally distributed with a mean of…

A: It is required to find the standard deviation of the distribution of hemoglobin levels in healthy…

Q: 2. The ages of the 189 people were recorded in a clinical study. The data have been partially…

A: The given data is as follows,…

Q: Dwight wants to estimate the mean calorie content in beets with 90% confidence.  He believes that…

A: The population standard deviation, sigma is 17. The z-critical value for the 90% confidence interval…

Q: The t-value of t = fall between -to.95 and to.95 because to.95

A: given that n = 13  sample mean =  1195 sample standard deviation = 169.3  population mean = 1016

Q: Please answer the problem applying the steps in testing hypothesis

A:

Q: An office manager claims that the mean time required to handle a customer complaint is more than 30…

A: To compare the population mean with the sample mean, either t or z tests would be perform. To use t…

Q: Americans (on average) individually eat 16 pounds of seafood each year with a standard deviation of…

A: Given that   x̄ = 14 , μ = 16 , ? = 7 , n = 4

Q: population of N = 10 scores has a mean of µ = 6. After one score is removed, the mean is found to be…

A: given data  population size (N) = 10 population mean ( μ) = 6 after removing one score : new mean =…

Q: A photoconductor film is manufactured at a nominal thickness of 25 mils. The pr increase the mean…

A: Solution: Given information: n1=8n2=8x1=1.15x2= 1.06s1=0.11s2= 0.09α=0.10

Q: A population has a mean of 250 and a standard deviation of 24. What value from the population has a…

A: Solution

Q: The manager at UPS feels that the weights of packages shipped recently are less than in he past.…

A: Given  Population mean μ=36.7, standard deviations σ=14.2, level of significance=0.01, n=64, sample…

Q: Individuals with calcium levels in the bottom  10%  of the population are considered to have low…

A: Consider X be a random variable that represent the calcium level. It is normally distritubuted with…

Q: ive a life expectancy of x = 71.5 years with a standard deviation of s, = 6.6 years. A sample of 6…

A: According to guidlines we can strickly answer three subspartsRural town:Sample size Sample mean…

Q: In the year 2033, katy perry is a leading traveling nurse. Katy is interested in reducing the mean…

A: Population mean, μ=8.6 Sample size, n=46 Sample mean, x¯=8.1  Sample sd, s=1.2 α=0.05

Q: From generation to generation, the mean age when smokers first start to smoke varies. A survey of 20…

A: Given Information :  From generation to generation, the mean age when smokers first start to smoke…

Q: Male and female populations of elephants under 80 years old are represented by age in the table…

A: Here the given table is : Age males…

Q: A sample has a mean of M=60 and a standard deviation of s=7.  For this sample, find the z-score for…

A:

Q: A California lake has been stocked with rainbow trout. These trout have an average length of 24…

A: Given Information: Mean μ=24 Standard deviation σ=3 Someone goes fishing and catches a trout that is…

Q: A population of scores has µ=44. In this population, a score of X= 40 corresponds to z= - 0. 50.…

A:

Q: t the residents of a local town reported sleeping an average of a=7.97 hours each night with a…

A: Given : sample mean= x̅ = 7.766 population mean=μ = 7.97

Q: A population of N=5 scores has a mean of μ=8. After one score is removed, the mean is found to be…

A: We have to find given missing score.

Q: Suppose that the hemoglobin levels among healthy females are normally distributed with a mean of 14.…

A: Question: Suppose that the hemoglobin levels among healthy females are normally distributed with a…

Confidence Intervals

When we calculate intervals in probability and statistics, it can be simply termed as finding out a confidence interval. The confidence interval is usually calculated from the data set which is observed. The value of the parameter that needs to be calculated is present here only.