Step 1 :Calculate the mean of the data, denoted as \(\bar{x}\).
Step 2 :Subtract the mean from each class midpoint \(x_i\) and square the result to get \((x_i - \bar{x})^2\).
Step 3 :Multiply each squared result by its corresponding frequency \(f_i\) to get \(f_i*(x_i - \bar{x})^2\).
Step 4 :Sum all the values from the previous step to get \(\sum_{i=1}^{n} f_i*(x_i - \bar{x})^2\).
Step 5 :Divide the result by the total number of data points minus 1, \(n-1\), to get \(\frac{\sum_{i=1}^{n} f_i*(x_i - \bar{x})^2}{n-1}\).
Step 6 :Take the square root of the result from the previous step to get the standard deviation \(s\), rounded to one decimal place.
Step 7 :Compare the calculated standard deviation \(s\) with the given standard deviation 11.1.