An electrical firm manufactures light bulbs that have a length of life that is approximately normally distributed with a standard deviation of 45 hours. How large a sample is needed if we wish to be 94% confident that our sample mean will be within 12 hours of the true mean? Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. Click here to view page 1 of the table of critical values of the t-distribution. Click here to view page 2 of the table of critical values of the t-distribution. The required sample size is. (Round up to the nearest whole number as needed.)

Q: The shape of the distribution of the time required to get an oil change at a 20-minute oil-change…

A: We have given that.    X~N( μ , ?^2 )    μ =21.8      , ? = 4.2   Z-score =( x - μ )/?

Q: The shape of the distribution of the time required to get an oil change at a 15-minute oil-change…

A: Given  μ=16.6, σ=4.4

Q: The shape of the distribution of the time required to get an oil change at a 20-minute oil-change…

A: Given information- Population mean, µ = 21.8 minutes Population standard deviation, σ = 4.2 minutes…

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A: Given that ; Mean = 88 wpm S. D = 10 wpm Here we use tha concept of standard normal distribution.

Q: According to a study conducted by an organization, the proportion of Americans who were afraid to…

A:

Q: Assume that the mathematics scores on the SAT are normally distributed with a mean of 500 and a…

A: Let X be the mathematics score in SAT exam. Therefore: X~Norm(μ=500, σ=100)

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A: Given that  X~Normal(μ=85,?=21.25) μ=85 , ?=21.25

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A: (c )

Q: The shape of the distribution of the time required to get an oil change at a 20-minute oil-change…

A: The shape of the distribution of the time required to get an oil change at a 20-minute oil-change…

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A:

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

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A: a) The claim is the male and female high school students have equal exam scores.

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Q: Suppose a sample of O-rings was obtained and the wall thickness (in inches) of each was recorded.…

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Q: Suppose a sample of O-rings was obtained and the wall thickness (in inches) of each was recorded.…

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A: Given: μ=92σ=10

Q: Suppose a geyser has a mean time between eruptions of 60 minutes. If the interval of time between…

A: From the given information, μ=60σ=14 c) n=26

Q: Suppose a sample of O-rings was obtained and the wall thickness (in inches) of each was recorded.…

A: Type the Rank in the excel as shown below Now, calculate the proportion as proportion=(Rank)(16+1)…

Q: Suppose a sample of O-rings was obtained and the wall thickness (in inches) of each was recorded.…

A: For the given data Select the correct choice

Q: For a normal population with a mean equal to 79 and a standard deviation equal to 19, determine the…

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Q: The manager of a paint supply store wants to determine whether the meah aHIUulTL manufacturer is…

A:

Q: The shape of the distribution of the time required to get an oil change at a 10-minute oil-change…

A:

Q: The reading speed of second grade students in a large city is approximately normal, with a mean of…

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Q: The finished inside diameter of a piston ring is normally distributed with a mean of 9 centimeters…

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Q: A data set includes 106106 body temperatures of healthy adult humans having a mean of…

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Q: The shape of the distribution of the time required to get an oil change at a 20-minute oil-change…

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Q: The annual per capita consumption fresh bananas (in pounds) in the United States can be…

A: Note: Thank you for the question. Since multiple questions are posted, according to our policy, we…

Q: A vending machine is designed to dispense a mean of 7.3 oz of coffee into an 8-oz cup. If the…

A: Follow step 2nd.

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

A: Solution

Q: A survey is planned to determine the mean annual family medical expenses of employees of a large…

A:

Q: Use the standand normal distribution table to determine the percent of data between z= - 0.92 and z=…

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Q: The mean exam score for 45 male high school students is 23.5 and the population standard deviation…

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Q: The reading speed of second grade students in a large city is approximately normal, with a mean of…

A: Given: mean = 88 Standard deviation  = 10

Q: Assume the annual day care cost per child is normally distributed with a mean of $6000 and a…

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Q: The shape of the distribution of the time required to get an oil change at a 20-minute oil-change…

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Q: The manager of a paint supply store wants to determine whether the mean amount of paint contained in…

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Q: The heights of a random sample of 50 college students showed a mean of 181.6 centimeters and a…

A: Solution