Question

The distribution of grades in an introductory finance class is normally distributed, with an expected grade of 70. If the standard deviation of grades is 10, in what range would you expect 99.00 percent of the grades to fall? (Round answers to 2 decimal places, e.g. 15.25. Hint: Think in terms of what the expected highest and lowest scores would be for 99.00% of the students taking the exam.) Excel Template (Note: This template includes the problem statement as it appears in your textbook. The problem assigned to you here may have different values. When using this template, copy the problem statement from this screen for easy reference to the values you've been given here, and be sure to update any values that may have been pre-entered in the template based on the textbook version of the problem.) 99.00 percent of the grades should fall beween the ranges (lower end) ....... and (upper end) ...

Answer 1

Based on 68-95-99 rule,

68% 95% 99% -30 +10 -20 -10 +20 +30

Confidence interval for 99% is Mean +/- 3 stanard deviation

Lower end range = 70 - (3 * 10) = 40

Upper end range = 70 + (3 * 10) = 100