jakolik wrote:

Professor Vasquez gave a quiz to two classes. Was the range of scores fro the first class equal to the range of scores for the second class?

(1) In each class, the number of students taking the quiz was 26, and the lowest score in each class was 70.

(2) In each class, the average (arithmetic mean) score on the quiz was 85

We need to determine whether the range of scores from the first class was equal to the range of scores from the second class.

Statement One Alone:

In each class, the number of students taking the quiz was 26, and the lowest score in each class was 70.

We see that each class had a lowest score of 70; however, without any information regarding the highest scores, statement one alone is not sufficient to answer the question.

Statement Two Alone:

In each class, the average (arithmetic mean) score on the quiz was 85.

Knowing the average score does not tell us anything about the range. Statement two alone is not sufficient to answer the question.

Statements One and Two Together:

Using both statements, we see that we only know the low end of the range. Without knowing the high end of the range, we cannot determine an answer. For instance, if all the students in both classes scored 85 on the exam, then the range in both classes is zero, and thus the ranges are equal. However, if in one of the classes one student scored 70, one student scored 100, and the rest scored 85, then the range in this class is 100 - 70 = 30, and thus the ranges may not be equal.

Answer: E

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