Find the variance and the standard deviation. Here are the

Problem 1.57

Find the variance and the standard deviation. Here are the scores on the first exam in an introductory statistics course for 10 students: 81 73 93 85 75 98 93 55 80 90 Find the variance and the standard deviation for these first-exam scores

Step by step solution:

Step 1:

The variance  of a set of observations is the average of the squares of the deviations of the observations from their mean, ie;

To find the mean