The distribution of grades on a certain test has a mean of 85.5 with a standard deviation of 11.2. There are 400 tests. Assuming that the grades are normally distributed, predict the number of students scoring between 75 and 95 . Use a table of area under the curve within $z$ standard deviations of the mean.

Question

Quizplus · Accepted Answer

The Answer of The distribution of grades on a certain test has a mean of 85.5 with a standard deviation of 11.2. There are 400 tests. Assuming that the grades are normally distributed, predict the number of students scoring between 75 and 95 . Use a table of area under the curve within $z$ standard deviations of the mean.

The Distribution of Grades on a Certain Test Has a Mean