Which fraction is the largest 9/10 11/12 11/13 7/10 8/10

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”?

Find the maximum value of p= 4x + 5y subject to the following constraints :

Harry is at the depot in dover and has deliveries to make in edinburgh, glasgow and aberdeen. from dover which of the deliveries is the shortest distance?