A Professor at a Local University Noted That the Grades

Short Answer

A professor at a local university noted that the grades of her students were normally distributed with a mean of 78 and a standard deviation of 10.
a.The professor has informed us that 16.6% of her students received grades of A. What is the minimum score needed to receive a grade of A?
b.If 12.1% of her students failed the course and received Fs, what was the maximum score among those who received an F?
c.If 33% of the students received grades of B or better (i.e., As and Bs), what is the minimum score of those who received a B?