Problem
Given the data set {3, 5, 7, 9}, find the quadratic mean (RMS).
Solution
Step 1 ：Step 1: Square each value in the data set and find the sum. \[3^2 + 5^2 + 7^2 + 9^2 = 9 + 25 + 49 + 81 = 164\]
Step 2 ：Step 2: Divide the sum by the number of values in the data set. \[\frac{164}{4} = 41\]
Step 3 ：Step 3: Take the square root of the result. \[\sqrt{41}\]
