A developmental psychologist would like to know whether success in one specific area can affect a person’s general self-esteem. The psychologist selects a sample of 25 ten-year-old children who all excel in athletics. These children are given a standardized self-esteem test. In the general population of ten-year-olds, the scores on the standardized self-esteem test are normally distributed with a mean of 70. The mean score for the sample is 72 with a standard deviation of 5. Correct decision and conclusion? Use the .05 significance level

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A:

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

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A: Given Information :  In 1955, Life Magazine reported that the 27 year-old mother of three worked, on…

Q: In 1955, Life Magazine reported that a 25-year-old mother of three worked, on average, an 80 hour…

A: From the provided information, Sample size (n) = 71 Sample mean (x̅) = 83 Sample standard deviation…

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A: Given data  X = time taken for computer repair company to diagnose a computer μ=50   σ=12…

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A:

Q: The standard deviation may not be greater than the mean. O True O False

A: False: standard deviations may be greater than mean  example: random variable x follow standard…

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A: From the provided information, Mean (µ) = 120.1 mmHg Standard deviation (σ) = 15.1 mmHg X~N (120.1,…

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Q: In 1955, Life Magazine reported that the 25 year-old mother of three worked, on average, an 80hour…

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A: Let Z be the standard normally distributed random variable with mean 0 and standard deviation 1.

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A: Solution: Let X be the number of miles between services. From the given information, X has mean…

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A:

Q: What is the z-score of a value of 27, given a set mean of 24, and a standard deviation of 2?

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A: Given X=65μ=60σ=6

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A: Given data , Admissions (x)                   P(x)     1000                               0.6…

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Q: What is the z-score of a value of 27, given a set mean of 24, and a standard deviation of 2?

A:

Q: Businesses such as General Mills, Kellogg's, and Betty Crocker regularly use coupons to build brand…

A: Note - As per our BNED policy, we are allowed to answer only three sub parts at a time. So, kindly…

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A: The mean of the data is μ=55 and the standard deviation is σ=11 It is also given that 20% of…

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A:

Q: The scores on a psychology exam were normally distributed with a mean of 59 and a standard…

A: Mean = 59 Standard deviation = 10 The formula for z is: z=x-μσ

Q: The question is attached in an image.

A: We have given that  Sample sizes n1= 36 , n2=45 , xbar1= 84 , xbar2 =79 ,s1=3.4 , s2= 2.6

Q: In 1955, Life Magazine reported that a 25-year-old mother of three worked (on average) an 80 hour…

A: As per honor code we will only answer first three parts. The sample size is greater than 30 and the…

Q: In 1955, Life Magazine reported that a 25-year-old mother of three worked (on average) an 80 hour…

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A: Z score is the distance of data point from its mean in terms of its standard deviation. It is…

Q: In preparation for the upcoming school year, a teacher looks at raw test scores on the statewide…

A: Formula of z score : z = x - μσ

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A:

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A: It is given that mean and standard deviation are 530 inches and 80, respectively.

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A: Given problem Given that   In a multiple-choice examination in Chemistry, students Mikasa and Jean…

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A:

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A: Solution: From the given information, z=1.45.

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A: Claim : the mean work week has increased for women

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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.