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An exam is given to students in an introductory statistics course. What is likely to be true of the shape of the histogram of scores if: a. the exam is quite easy? b. the exam is quite difficult? c. half the students in the class have had calculus, the other half have had no prior college math courses, and the exam emphasizes mathematical manipulation? Explain your reasoning in each case.

Short Answer

Expert verified
Case(a) will produce a negatively skewed distribution. Case(b) will produce a positively skewed distribution. Case (c) will produce a bimodal distribution.

Step by step solution

01

Analysis of case (a): Exam is Easy

If the exam is quite easy, the majority of students would score high. Therefore, there would be a larger concentration of scores on the higher end of the histogram. This would result in a negatively skewed or left-skewed distribution.
02

Analysis of case (b): Exam is Difficult

On the contrary, if the exam is quite difficult, the majority of students would score low. This means the majority of the scores would be on the lower end of the scale, resulting in a positively skewed or right-skewed distribution.
03

Analysis of case (c): Mixed Backgrounds

If half the students have had calculus (presumably making them better prepared for a mathematics-based exam) and the other half has had no prior college math courses, there would likely be a bimodal distribution. This means there would be two peaks on the histogram: one for the calculus-prepared students, likely scoring higher, and one for the students with no college-level math background, likely scoring lower.

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