Professor such noted that the grades of his students were no

Professor such noted that the grades of his students were normally distributed with a mean of 78 and a standard deviation of 10. Professor Such has informed students that 18 percent of his students received grades of A. What is the minimum score needed to receive a grade of A? If 18 percent of his students failed the course and revived D or lower, what was the minimum score to pass the course?

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