It has been observed that a random variable follows a normal distribution with a mean of 80, and a standard deviation of 120. Find: (i) P(228.8 < X< 398) (ii) What is the probability that X is greater than 135.2?

Q: A normally distributed population with unknown variance has a mean of 20. If you took a random…

A: Given,  X is normally distributed with mean μ=20 and variance is unknown. A random sample of size…

Q: If a normal distribution has a mean of 28.0 and a standard deviation of 2.5, what is the value of…

A: Given information Mean µ = 28 Standard deviation σ = 2.5 Using standard normal table,

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A:

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A: Using z-score table to calculating above. Z-score=(X-mean)/standard deviation

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A: The following information has been provided:

Q: A normal distribution has a mean of μ =64 and a standard deviation of σ = 8. What is the probability…

A:

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A: Given data,μ=190σ=22P(X&gt;160)=?

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A: Given, μ = 450σ = 150To find,P (X &gt; 700) = ?

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A:

Q: A group of data has a mean of 65 with a standard deviation of 5. What z-score is possible if the…

A: According to the provided information,

Q: What is the Z score of an individual with a height of 183cm if the mean of the population is 170cm…

A: Given that mean = 170 SD = 6.1 And the height of individual X = 183

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A: The random variable X is defined as the student will have a raw score which follows normal…

Q: A normal distribution has a mean of µ = 70 with σ = 12. If one score is randomly selected from this…

A: According to the provided information,

Q: The mean of a normally distributed random variable is always bigger than its standard deviation.…

A: FALSE.  Explanation: Generally, the mean of a Normal distribution is higher than the standard…

Q: Based on the records of the Admissions Office of University X, the mean score of all Grade 11…

A:

Q: X is Normally distributed with a mean of 500 and a standard deviation of 40. What is the value of…

A: X is normally distributed. and X~N(μ,σ)where  mean(μ)=500      and standard deviation(σ)=40find x?…

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A: Central Limit Theorem for mean:If a random sample of size n is taken from a population having mean µ…

Q: Suppose that y is a random variable having a normal distribution with a mean equal to 250 and a…

A: Solution: It is given that the random variable y follows the normal distribution with mean and…

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A: Given that, Mean = 88 Standard deviation = 12

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Q: What is the z-score of x = 11, if it is 2.5 standard deviations to the left of the mean?

A:

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Q: If a z-score is equal to −2.05, it is 2.05 standard deviations below the mean. True or False

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A: Given: X is a normal random variable with standard deviation equals to 10.

Q: Suppose x has a normal with mean =20 and standard deviation =12. If you draw a random samples of…

A: Given: x~N(μ,σ)μ=20σ=12

Q: A normal distribution has a mean of μ= 54 and a standard deviation of σ=6 What is the probability of…

A: The sample size is, n = 36 The values of mean and standard deviation of the sampling distribution…

Q: What is the z-score of x = 9, if it is 0.133 standard deviations to the left of the mean?

A: Given X=9,

Q: what is the probability that a randomly selected case falls between 60 and 68? And what is the value…

A: It is given that X follows N(mean = 72, SD = 12), then Z = (X - mean)/SD follows N(0,1)

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Q: Given that pregnancies have a mean of 266 days and standard deviation of 16 days, it is found that…

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Q: A normal distribution has a mean of μ =72 and a standard deviation of σ = 8. What is the probability…

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Q: (a) The standard deviation is greater than the mean for each of these samples. Explain why it is not…

A:

Q: Suppose the scores, x, on a college entrance examination are normally distributed with a mean of…

A: Solution: Let X be the score on a college entrance examination. From the given information, X…

Q: In a population with a mean of μ = 50 and a standard deviation of σ = 10, would a score of X = 58 be…

A: Given in a population with a mean of μ=50, and a standard deviation of σ=10, a score of X=58

Q: In a normal distribution with a mean of 72 and a standard deviation of 12:   What percentage of…

A: Given that , mean = μ = 72 standard deviation = σ = 12

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Q: In a test taken by a large number of students, the average score of the test takers is 90 and the…

A: The mean is 90 and the standard deviation is 4.

Q: The mean weight of 18-year-old females is 126 pounds, and the standard deviation is 15.7. If a…

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Q: "suppose that a random sample of size 20 is taken from a normal distribution with unknown variance…

A: Given: n=20 μ=Unknownx=10σ2=1Andμ(Posterior)=15σ(Posterior)=0.1

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Q: IQ scores are normally distributed with a mean of 110 and a standard deviation of 2.9. In a sample…

A: For the solution of the problem follow the next step.

Q: A normal distribution has a mean of µ = 40 with σ = 8. If one score is randomly selected from this…

A: A normal distribution has a mean of µ = 40 with σ = 8.