In a law office, the average number of billed hours per day was 146 last year. In the first 71 days of this year, the average number of billed hours per day is 157 with a standard deviation of 52 hours. When testing the hypothesis (at the 10% level of signficance) that the average number of billed hours per day has increased, what test statistic? (please round your answer to 2 decimal places)

Q: A mandatory competency test for high school sophomores has a normal distribution with a mean of…

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A:

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A:

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Q: The Wechsler IQ test is normally distributed with mean 100 points and standard deviation 15 points.…

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A: Given,mean(μ)=120standard devition(σ)=20

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A: Kwe have to find out given probabiity..

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Q: The Psych 230 students finished the course with a total population mean of 130 points and the…

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Q: An IQ test has a mean of 100 and a standard deviation of 15. An elite engineering company wants to…

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Q: Can the standard deviation of a data set be zero

A: Standard deviation can not be negative.

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Q: A recent study found that 69% of all adults over 50 wear sunglasses for driving. In a random sample…

A: Formula : Mean = np Standard Deviation  :

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Q: The Wechsler IQ test is normally distributed with mean 100 points and standard deviation 15 points.…

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