Scores on a standardized exam are known to follow a normal distribution with standard deviation o = 21. A researcher randomly selects 75 students and computes their average score. He reports that the mean score is 73.4, with a margin of error of 5.641. How confident are you that the mean score for all students taking the exam is in the interval (67.759, 79.041)? Confidence =

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A: Given: A distribution of values is normal with  μ=123.2 , σ=62

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A: Suppose a random variable X, defines the scores in competency test for high school sophomores.

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A: The mean is 35 minutes and the standard deviation is 3.

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A: given data μ = 1200σ = 60 normal distributionn = 64P(1200<x¯<1214) = ?

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A: The mean is 8.2 minutes and the standard deviation is 1 minute.

Q: samples of n = 100 from

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A: Let x be the score which follows normal distribution with mean 80 and standard deviation 20. The…

Q: The mean of a test is 400 and the standard deviation is 75. It is normally distributed. A sample of…

A: 1] Mean μ=400 2] standard deviation σ=75 3] n=25 4] μx¯=400σx¯=σn=7525=15

Q: The mean number of English courses taken in a two-year time period by male and female college…

A: From the Part (iii), the null hypothesis is rejected.

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Q: ly normal and has a standard deviation of 88% of students scored above a 800. What is the mean of

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Q: mandatory competency test for high school sophomores has a normal distribution with a mean of  425…

A: Given that.   X~N( μ , ?)   μ=425     , ?=83   Z-score =( x - μ )/?

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A:

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A: It is given that the mean is 105 and standard deviation is 13.

Q: The MF exam has a population mean of 500 and a standard deviation of 200. What are the scores for…

A: Let X=MF exam scores We have given information, The population mean μ=500 And population standard…

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Q: The SAT Math scores have a bell-shaped distribution with a Mean of 567 and a Standard Deviation of…

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A: Given information- Population mean, µ = 1050 mm Population standard deviation, σ = 400 mm Let, X be…