A large group of students took a test in Statistics and Probability and the final grades have a mean of 70 and a standard deviation of 10. If we can approximate the distribution of these grades by a normal distribution, what percent of the students; a. scored higher than 80? b. should pass the test (grades≥60)? c. should fail the test (grades<60)?

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A: Given that.   X~N( μ , ?)   μ=130     , ?=5  , x=143   Z-score =( x - μ )/?

Q: A significant number of students completed a Statistics exam, and the final marks had a mean of 70…

A: Answer - A significant number of students completed a Statistics exam, and the final marks had a…

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A: Given Information: Mean, μ=74 Standard Deviation, σ=15 Sample Size, n=36

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A: The objective of this question is to find the percentage of Asian elephant pregnancies that are…

Q: A distribution consists of three requencies 250, 300, 350 having neans 30, 15 and 20 and standard…

A: We have given that  Size N1=250 , N2=300, N3=350 Sample mean xbar1 =30 , x2=15 , x3=20 Standard…

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A: We have given that.   X~N( μ , ?^2 )   μ =350 , ? =25   Z-score =( x - μ )/?

Q: If the scores follow normal distribution with a mean of 120, a standard deviation of 10, find…

A: Solution

Q: Suppose the prevalence of type II diabetes in a community is 36%. Researchers want to sample 16…

A:

Q: Assume that the mathematics scores on the SAT are normally distributed with a mean of 500 and a…

A: The mean is 500 and the standard deviation is 100.

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A: Given :  Mean(μ)=30 and N=3

Q: What proportion of the students scored lower than 80 if the distribution of these grades can be…

A:

Q: The mean and standard deviation of the sampling distribution of the mean is shown as?

A:

Q: A certain standardized tests math scores have a bell shaped distribution with a mean of 525 and a…

A: GivenMean(μ)=525standard deviation(σ)=105

Q: Assume that the mathematics scores on the SAT are normally distributed with a mean of 500 and a…

A:

Q: In a normal distribution, mean is 60 and standard deviation is 5. How many of the cases have scores…

A: The probability between two specific numbers a and b in a normal distribution with mean μ and…

Q: An instructor in a large lecture class found, at the end of the semester, that the total point…

A: The provided information is:

Q: ominic would want to estimate the mean of a population which is normally distributed. The standard…

A:

Q: Assume that the mathematics scores on the SAT are normally distributed with a mean of 500 and a…

A: normal distributionμ = 500σ = 100P(570&lt;x&lt;640) = ?

Q: tal of 82 Grade 11 students of ABC senior high school took the 60 item test in General mathematics.…

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Q: A set of data item is normally distributed with a mean 208 and a standard deviation of 48. Find the…

A:

Q: The sizes of houses in Kenton County are normally distributed with a mean of 1369 square feet with a…

A: From the given information, the mean and standard deviation are 1,369 and 171.

Q: If the standard error,  of a sample data set is 5 and the standard deviation,  of the distribution…

A: For a population with mean µ  and standard deviation σ, the standard error is σx̅ = σ/√n, where x̅…

Q: Suppose the test scores in a class are normally distributed with a mean of 70 and a standard…

A: The Z-score of a random variable X is defined as follows: Z = (X – µ)/σ. Here, µ and σ are the mean…

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A: Standard normal distribution: The standard normal distribution is a special case of normal…

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

A:

Q: The distribution of grades in a final exam conforms to the normal distribution with an average of 60…

A: Given information: μ=60σ=8 The proportion of students required to pass=300350=0.857142857≈0.8571

Q: Suppose that the score on a reading test are normally distributed within a mean of 70 and a standard…

A:

Q: Suppose that a distribution of 300 items has mean 115 and standard deviation 4. Find the z-score of…

A: Given, mean (μ) = 115 standard deviation (σ) = 4 x = 121

Q: At a large university, data were collected on the number of sisters and brothers that each student…

A: The objective of the question is to find the mean of the distribution of the sum of two random…

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.