A case of wood screws weights LaTeX: 18\frac{2}{3}\:18 2 3 pounds. Each individual box of wood screws weighs LaTeX: 1\frac{1}{3}1 1 3 pounds. How many boxes are in the case?

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?