Question

At XYZ University, another group of students was selected and asked how much of their weekly allowance they spent in buying mobile phone load. The following is the list of amounts spent: Php 200, 180, 30, 20, 10, 160, 150, 80. find the standard deviation

Answer 1

Mean: $\frac{1}{n}\Sigma x_i=\frac{830}{8}=103.75.$

Variance: $\sigma^2=\frac{1}{n} \Sigma(x_i-\mu)^2=\frac{42187.5}{8}=5273.4375.$

Standard deviation: $\sigma=\sqrt{5273.4375}=72.6184.$