math
posted by Kate .
Miss C gives a test to the 10 students in her firstperiod algebra class. The grades are
93,82,95,86,90,84,89,79,87,93
A. Find the mean and Standard Deviation of the 10 scores.
B. List all the reasons for why the late class could have a different mean or standard deviation

A. Find the mean first = sum of scores/number of scores
Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.
Standard deviation = square root of variance
B. Inadequate data
I'll let you do the calculations.