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91Ó°ÊÓ

Anna, a language major, took final exams in both French and Spanish and scored 83 on each. Her roommate Megan, also taking both courses, scored 77 on the French exam and 95 on the Spanish exam. Overall, student scores on the French exam had a mean of 81 and a standard deviation of \(5,\) and the Spanish scores had a mean of 74 and a standard deviation of 15 . a. To qualify for language honors, a major must maintain at least an 85 average for all language courses taken. So far, which student qualifies? b. Which student's overall performance was better?

Short Answer

Expert verified
For part a, Megan qualifies for the language honors as her average is above 85, Anna does not. For part b, based on the z-score comparison, Megan's overall performance was better than Anna's.

Step by step solution

01

- Determine each student's average score

First, calculate the average score for each student in both courses. For Anna, the average is \((83+83)/2 = 83\). For Megan, the average is \((77+95)/2 = 86\). Compare each average with the set standard of 85 to determine who qualifies for language honors.
02

- Calculate the Z-scores

Next, calculate the z-score for each student in each course. The z-score formula again is \(Z = (X - μ)/σ\). For French, Anna's Z is \((83-81)/5 = 0.4\) and Megan's Z is \((77-81)/5 = -0.8\). For Spanish, Anna's Z is \((83-74)/15 = 0.6\) and Megan's Z is \((95-74)/15 = 1.4\).
03

- Compare the Z-scores

Finally, compare the z-scores. The student with the higher z-score in each course is doing better compared to others. After calculating, Megan has a higher z-score than Anna in both courses. Therefore, Megan's overall performance is better despite having a lower score in French exam.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Z-score
A Z-score is a statistical tool that tells us how many standard deviations a data point is from the mean of the data set. It helps us understand the position of a single score in the context of a group of scores, which is very useful in educational assessment contexts. For example, if a score's Z-score is 0, it is exactly at the mean. A positive Z-score indicates that the score is above the mean, and a negative Z-score indicates that the score is below the mean.
In Anna and Megan's case, their Z-scores in French and Spanish indicate how well they performed relative to their peers.
  • Anna's French Z-score of 0.4 means she scored 0.4 standard deviations above the mean.
  • Megan's French Z-score of -0.8 shows she scored 0.8 standard deviations below the mean.
Comparatively, for Spanish, with Z-scores of 0.6 for Anna and 1.4 for Megan, it shows Megan did better as she scored further above the mean.
Standard Deviation
Standard deviation is a measure of the amount of variation or spread in a set of values. In educational assessments, it helps to understand how spread out the scores are in any exam or test.
The formula for standard deviation allows us to see where scores lie about the mean, making it easier to identify whether a score is typical or unusual.
In the given exercise, the standard deviation for the French exam is 5, indicating that most students' scores are within 5 points of the mean (81).
For the Spanish exam, the standard deviation is 15, indicating more variability in scores, meaning some students scored much higher or lower than the mean of 74.
Mean Score
The mean score, often referred to as the average, is the sum of all the scores divided by the number of scores. In educational contexts, the mean score provides a quick snapshot of a class's overall performance in a particular exam.
The mean helps to establish benchmarks or standards for academic performance.
For Anna and Megan, calculating their mean scores in both exams was crucial for determining eligibility for language honors.
  • Anna's mean score was 83, which did not qualify her for honors.
  • Megan's mean score was 86, making her eligible for honors.
Mean scores are straightforward to calculate but give a lot of valuable information on whether a student meets certain academic standards.
Educational Assessment
Educational assessment is the systematic evaluation of student learning and performance, typically with the help of tests and exams. Tools like Z-scores, standard deviation, and mean scores are essential in these assessments to provide a fair and contextual view of a student's performance.
Through assessment, educators can identify students' strengths and weaknesses, qualifying them for honors or identifying areas needing improvement.
In the exercise, Z-scores helped evaluate Anna and Megan's performance beyond just raw scores.
  • By understanding their relative performance compared to their peers, Megan was recognized as the better performing student overall.
Educational assessments provide the data needed to support students in their academic journey, enhancing their learning outcomes.

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Most popular questions from this chapter

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