Last year, the numbers of skateboards produced per day at a certain factory were normally distributed with a mean of 20,500 skateboards and a standard deviation of 55 skateboards. On what percent of the days last year did the factory produce 20,555 skateboards or fewer?  On what percent of the days last year did the factory produce 20,610 skateboards or more? On what percent of the days last year did the factory produce 20,445 skateboards or fewer?

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Q: Last year, the numbers of skateboards produced per day at a certain factory were normally…

A: Here we use the formula ; z=(x-mean)/standard deviation

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A: Solution

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A: Given that, mean, mu=270 Standard deviation, sigma= 75 We know that, Z score=(X-mu)/sigma

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Q: Last year the numbers of skateboards produce per day at a certain factory or normally distributed…

A: Given,   Mean = 20300 Standard deviation = 52

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A:

Q: A tire company finds the lifespan for one brand of its tires is normally distributed with a mean of…

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A: It is given that the mean and standard deviation are $300 and $50, respectively.

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A: Given that, In 2011, the national percent of low-income working families had an approximately normal…

Q: In 2011, the national percent of low-income working families had an approximately normal…

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A: Given : population mean , u = 3.10  population standard deviation, σ = 0.54

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A:

Q: According to the 2019 National Apartment List Rent Report, the average two-bedroom apartment rent in…

A: Given that, Mean = 1460 Standard deviation = 100 Sample size = 64

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A: Given,mean(μ)=31.28standard deviation(σ)=11.42sample size(n)=10

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Q: One researcher collected a sample of expenses for advertisement from 5 companies as follows: 50, 60,…

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A:

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A:

Q: According to the Department of Education, the time college students spend on their cell phones daily…

A: GivenMean(μ)=270standard deviation(σ)=75

Q: The daily number of bad checks received by a large department store in a random sample of 5 days out…

A: Given sample data,   Standard deviation =?

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.