Scores on the math SAT are normally distributed. A sample of 20 SAT scores had standard deviation s = 87. Someone says that the scoring system for the SAT is designed so that the population standard deviation will be σ = 100. Do these data provide sufficient evidence to contradict this claim?

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A:

Q: the variance and standard deviation are based on the________________?

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A: Given data, Mean = 69 SD = 7

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A: For the given data Perform one sample t test

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A: The standard deviation is 20.

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A:

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Q: I don't understand how to solve for this. I'm having trouble understanding the percentages

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Q: In an exam for a statistics class, the class average is 68 with a standard deviation 4. If a student…

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A:

Q: Suppose that the scores on a statewide standardized test are normally distributed with a mean of 71…

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Q: In a large section of a statistics​ class, the points for the final exam are normally​ distributed,…

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A: Given that  X~Normal(μ =500 , ? =100) X=SAT score  Z-score=(X-μ)/?

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Q: For a sample, a score that is 12 points above the mean has a z-score of z = 1.20. What is the sample…

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Q: Suppose that the scores on a statewide standardized test are normally distributed with a mean of 69…

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Q: A statistics professor announces that 15% of the grades he gives are As.  The results of the final…

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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.