Afarmer has 9 2/5 acres of land. if he sells 1 1/3 acres to his neighbor, how many acres of land does he have left?

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”?