Solution:
1. Arrange a set of data in ascending order.
\(15,20,25,26,27,36,50\)
2. Apply \(\text{Range} = \text{Largest value} - \text{Smallest value}\)
\(\therefore 50 -15 = 35.\)
Variance
\(\sigma^2= \dfrac{\sum (x- \bar{x})}{N}\)
Standard deviation
\(\sigma= \sqrt{\dfrac{\sum (x- \bar{x})}{N}}\) or \(\sigma= \sqrt{\dfrac{\sum x^2}{N}-\bar{x}^2}\)
Treat yourself with rewards for your hard work