Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

An elementary school class ran 1mile in an average of 11 minutes with a standard

ID: 2956559 • Letter: A

Question

An elementary school class ran 1mile in an average of 11 minutes with a standard deviation of 3minutes. Rachel, a student in the class, ran 1mile in 8 minutes. A junior high school class ran 1mile in an average of 9minutes, with a standard deviation of 2minutes. Kenji, a student in the class, ran 1mile in 8.5 minutes. A high school class ran 1mile in an average of 7 minutes with a standard deviation of 4minutes. Nedda, a student in the class, ran 1mile in 8minutes.

a. Why is Kenji considered a better runner than Nedda, even though Nedda ran faster than him?

b. Who is the fastest runner with respect to his or her class? Explain why.

Explanation / Answer

a. Kenji ran faster than the class average by .25 of a standard deviation while Nedda was slower than the average in her class. b. Rachel: average -1st dev Kenji: average-.25stdev Nedda: slower than average so it's definitely not her Since Rachel is faster than the average and differs by the most standard deviations compared with Kenji, Rachel is the faster one.