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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”?

In which direction does the left side of the graph of this function point? a(x) = 3x - x2 + 4x - 2

What fraction is equivalent to 0.46464646··· a. 46⁄99 b. 46⁄999 c. 46⁄100 d. 23⁄50