Answer:

A frequency distribution is a chart that shows how frequently different values occur in a set of data. The frequency distribution below shows the grades of 25 students in a class. The grades range from 78-92.

a) Range: The range of the grades is 92-78, or 14. This means that the highest grade is 92 and the lowest grade is 78.

b) Variance: Variance is a measure of how spread out the data is. In this case, the variance of the grades is 30.8.

c) Standard Deviation: Standard deviation is a measure of how much variation there is in the data. The standard deviation of the grades is 5.53.

Overall, the frequency distribution shows that the grades of the 25 students vary significantly, with the range being 14 and the standard deviation being 5.53. This means that there is a lot of variation in the grades, with some students having grades as low as 78 and others as high as 92.