If Sarah scored 78 on her history test which had a mean of 70 and a standard deviation of 3 and she scored 84 on her math test which had a mean of 80 and a standard deviation of 2, on which test did she score better

Q: Suppose a sample of 60 business majors revealed that the average time spent studying per week is 22…

A: A Z-score is a numerical measurement that describes a value's relationship to the mean of a group of…

Q: One year Thomas had the lowest ERA (earned-run average, mean number of runs yielded per nine innings…

A:

Q: One year Thomas had the lowest ERA​ (earned-run average, mean number of runs yielded per nine…

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

Q: If IQ scores are normally distributed with a mean of 100 and standard deviation of 12, what does…

A: The normal distribution is symmetric in nature having parameters μ and σ.The mean, mode, and median…

Q: Kimberly and Alexis began arguing about who did better on their tests, but they couldn't decide who…

A: Given data,For mathμ=76.8σ=9.9Kimberly score is X=76.4For Socialμ=62.6σ=9Alexis score is X=63.2

Q: Raul received a score of 77 on a history test for which the class mean was 70 with a standard…

A: for history test:mean(μh)=70standard deviation(σh)=4and xh=77For biology test:mean(μb)=70standard…

Q: Suppose there are two groups of students. Group A and Group B both have an average height of…

A: Here there are two groups of students are given named as A and B. And the given parameters of A and…

Q: Suppose that the scores on a reading ability test are normally distributed with a mean of  60  and…

A:

Q: The daily commuter to work for a section of interstate has a mean of 22 minutes and a standard…

A:

Q: Juwan and Salvador began arguing about who did better on their tests, but they couldn't decide who…

A: Here we need to compute the z score of Salvador and Juwan and find who performed relatively better…

Q: One year Sam had the lowest ERA (earned-run average, mean number of runs yielded per nine innings…

A: From the provided information, The mean and standard deviation for the males ERA are as follow: Mean…

Q: Suppose you are told that a computer programmer in Portugal who makes $809.40 has a z-score of -0.50…

A: Solution: It is given that a computer programmer in Portugal who makes $809.40 has a z-score of…

Q: The U.S. Bureau of Labor statistics reports that the average annual expenditure on food and drink…

A: Given Information: Mean μ=$5700 Standard deviation σ=$1500 To find the percentage of families who…

Q: A mathematics professor gives two different tests to two sections of his college algebra courses.…

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

Q: Nina and Amy began arguing about who did better on their tests, but they couldn't decide who did…

A: Given: All the student’s test grades in the English All the student’s test grades in the Society…

Q: Find their respective​ z-scores. Which player had the better year relative to their​ peers, Hank or…

A: Given For males, μ=4.296σ=0.907 For females μ=3.764σ=0.866

Q: Natalie and Stephanie began arguing about who did better on their tests, but they couldn't decide…

A:

Q: student a received a score of 91 on a test whose scores had a mean of 82 and a standard deviation of…

A: Given data,For Student AMean μ=82sd      σ=6Score is x=91For Student BMean μ=80sd      σ=4Score is…

Q: Juwan and Aaron began arguing about who did better on their tests, but they couldn't decide who did…

A:

Q: A psychologist who needs two groups of students for a learning experiment decides to select a…

A: Hi! Thank you for the question. AS per the honor code, we are allowed to answer the three sub-parts…

Q: The principal decided that the top 30% of the class with the highest grades in statistics will be…

A:

Q: Ted had the lowest ERA​ (earned-run average, mean number of runs yielded per nine innings​ pitched)…

A: According to the given information in this question We need to find the z score

Q: a standard deviation of 9.8, and all the students' test grades in Social Studies had a mean of 63.4…

A: Given : a) For Lauren Test value =x= 75 population mean=μ = 76.4 population standard…

Q: If the highest paid soccer platyer has his salary doubled, which of these will change? Can you…

A: We have to find correct options which will change.

Q: The scores for a standardized reading test are found to be normally distributed with a mean of 300…

A: Given : mean = μ = 300 standard deviation = σ = 40 sample size = n = 490

Q: Erik and Juan began arguing about who did better on their tests, but they couldn't decide who did…

A:

Q: The mean and standard deviation of 20 items was found to be 10 and 2 respectively. Later it was…

A:

Q: a) Calculate the z-score for Lucas's test grade. z=z= b) Calculate the z-score for Alex's test…

A:

Q: The scores on a university examination are normally distributed with a mean of 70 and a standard…

A: The scores of a university are normally distributed with mean 70 and s standard deviation 10.Given…

Q: For a group of 100 candidates the mean and standard deviation of their marks were found to be 60 and…

A: 1] n=100 2] X¯=603] Standrd deviation σ=154] σ2=225

Q: The mean score of a statistics exam of class A is 75 with a standard deviation of 13 while class B…

A: It is given, Mean score of statistics exam = 75 SD of statistics exam = 13 Mean score of statistics…

Q: What percent of the students received a score below 64, if the mean grade on a test was 70 and the…

A:

Q: The Jackson triplets , Jenny , John and James , are in different algebra classes at city high . On…

A: The information about the final exams of Jackson triplets is provided as follows:   Xi μi σi…

Q: One year Perry had the lowest ERA (earned-run average, mean number of runs yielded per nine innings…

A: Given: For males, the mean ERA μ is 3.771 and standard deviation σ is 0.861. The mean ERA of Perry…

Q: The tallest living man at one time had a height of 244 cm. The shortest living man at that time had…

A: Given : Heights of men at that time had a mean of 174.73 cm and a standard deviation of 6.23 cm.

Q: A student obtained the mean and standard deviation of 100 observations as 40 and 5 respectively. It…

A:

Q: if an average score of exams was 74 points for 24 students  the 25th student got 64 points whats…

A:

Q: The average age of senators in the 108th Congress was 58 years. If the standard deviation was 11…

A: Average or mean (μ) = 58 years and standard deviation (σ) = 11 years  Then, We will find the z…

Q: Suppose you received a score of 95 out of 100on exam 11 . The mean was 79and the standard deviation…

A:

Q: The cholesterol levels of a group of young women at a university are normally distributed, with a…

A: A normal distribution is a continuous distribution which has many real life applications. A standard…

Q: According to the IRS, the average refund issued by the IRS in the 2019 filing season is $1,949.…

A: Given that, Mean = 1949 Standard deviation = 712 Sample size = 64

Q: he scores in a test conducted to 500 students are normally distributed with a mean of 110 and a…

A: Given that  The scores in a test conducted to 500 students . The scores are normally distributed…

Q: My Physics professor announced that top 18% will get A in the class.               Class mean is 72,…

A: Let X= score of a student  Given that X follows a normal distribution with mean=72 and standard…

Q: The combined math and verbal scores for students taking a national standardized examination for…

A:

Q: The mean score on the Stats exam was 75 points with a standard deviation of 5 points, and Gregor’s…

A: The mean score on the Stats exam was 75 points with a standard deviation of 5 points, and Gregor’s…

Q: John finds that there is a scholarship available to all persons scoring in the top 5 % on the ACT…

A:

Q: Suppose the midterm exam score for 100 students at UPC had a mean of 70 and a standard deviation of…

A:

Q: A person’s IQ must be in the upper 2% of the population to be considered into the Honor Society.  If…

A: Given Information: A person’s IQ must be in the upper 2% of the population to be considered into the…

Q: In ABC High School, the mean IQ test score of the first year students is 102 and the standard…

A: For the given data  What is the z-score of a student whose IQ test score is 106?

Q: Nick and Donald began arguing about who did better on their tests, but they couldn't decide who did…

A: Givennick test grade in science is 79.6x=79.6science mean(μ)=73.8standard deviation(σ)=9.3Donald…

Inverse Normal Distribution

The method used for finding the corresponding z-critical value in a normal distribution using the known probability is said to be an inverse normal distribution. The inverse normal distribution is a continuous probability distribution with a family of two parameters.

Mean, Median, Mode

It is a descriptive summary of a data set. It can be defined by using some of the measures. The central tendencies do not provide information regarding individual data from the dataset. However, they give a summary of the data set. The central tendency or measure of central tendency is a central or typical value for a probability distribution.

Z-Scores

A z-score is a unit of measurement used in statistics to describe the position of a raw score in terms of its distance from the mean, measured with reference to standard deviation from the mean. Z-scores are useful in statistics because they allow comparison between two scores that belong to different normal distributions.