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 300 with a standard deviation of 30 on a standardized test. Assuming a non-mound-shaped distribution, what percentage of the students scored over 390?
A) approximately 2.5 B) at least 89
C) at most 5.5 D) at most 11
Question 2
50 students were randomly sampled and asked questions about their exercise habits. One of the questions they were asked concerned the frequency of exercise, defined to be the number of times they exercised in a week. This variable would be characterized as which type of random variable?
A) continuous B) discrete
