Question

A study was designed to investigate the effects of two variables--(1) a student’s level of mathematical anxiety and (2) teaching method--on a student’s achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 450 with a standard deviation of 30 on a standardized test. The test scores follow a normal distribution.

Answer 1

Using the Empirical Rule, it is found that approximately 68% of the students would score between 420 and 480.

The Empirical Rule states that for a normal variable:

• 68% of the measures are within 1 standard deviation of the mean.

• 95% are within 2.

• 99.7% are within 3.

In this problem, the mean is of 450 while the standard deviation is of 30.

450 - 30 = 420

450 + 30 = 480

Hence, approximately 68% of the students would score between 420 and 480.

A similar problem is given at https://brainly.com/question/25807482